Projection exposure apparatus and method, catadioptric optical system and manufacturing method of devices

ABSTRACT

A projection exposure apparatus includes a projection optical system, which is arranged in an optical path between a first surface and a second surface, projects a pattern on a negative plate arranged on the first surface onto a workpiece arranged on the second surface and exposes the pattern thereon. The projection optical system includes a first imaging optical subsystem having a dioptric imaging optical system; a second imaging optical subsystem having a concave reflecting system; a third imaging optical subsystem having a dioptric imaging optical system; a first folding mirror arranged in an optical path between the first imaging optical subsystem and the second imaging optical subsystem; and a second folding mirror arranged in an optical path between the second imaging optical subsystem and the third imaging optical subsystem. The first imaging optical subsystem forms a first intermediate image of the first surface into the optical path between the first imaging optical subsystem and the second imaging optical subsystem. The second imaging optical subsystem forms a second intermediate image of the first surface into the optical path between the second imaging optical subsystem and the third imaging optical subsystem.

TECHNICAL FIELD

[0001] The present invention relates to a projection exposure apparatusand method used in transferring a negative plate (mask, reticle and thelike) onto a workpiece (substrate and the like) in a photolithographicprocess for manufacturing devices, such as semiconductor devices, imagepickup devices, liquid crystal display devices or thin-film magneticheads and so on and relates to a high-resolution catadioptric typeprojection optical system suitable for such projection exposureapparatus.

BACKGROUND ART

[0002] In the photolithographic process for manufacturing semiconductordevices and so on, projection exposure apparatus in which a patternimage of a photomask or a reticle (generically called “reticle”hereafter) is exposed onto a workpiece such as a wafer, or a glass plateand the like coated with a photoresist and the like via projectionoptical system have been used. Then, the resolving power (resolution)required for the projection optical system of the projection exposureapparatus has been increased more and more in order to improve theintegration level of semiconductor devices and so on. As a result, thewavelength of illuminating light (exposure light) must be shortened andthe numerical aperture (NA) of the projection optical system must beincreased.

[0003] For example, if an exposure light with wavelength of 180 nm orless is used, it is possible to achieve a high resolution of 0.1 μm orless. However, if the wavelength of illuminating light is shortened, theabsorption of light becomes remarkable, and the kinds of glass materials(optical materials) that can be practically used are limited. Inparticular, if the wavelength of illuminating light becomes 180 nm orless, the practically usable glass material is limited to fluorite only.As a result, the correction of chromatic aberrations becomes impossiblein a dioptric type projection optical system. Here, the dioptric typeoptical system is an optical system which does not contain reflectivesurfaces (concave reflective mirrors and convex reflective mirrors) withpower, but only contains transmissive optical members, such as lenscomponents.

[0004] As described above, there is a limit to the allowable chromaticaberrations in a dioptric type projection optical system, and a verynarrow band of laser light source is needed. In this case, an increasein the cost of laser light source and a decrease of its output areunavoidable. Moreover, many positive lenses and negative lenses must bearranged in a dioptric optical system to bring the Petzval sum, whichaffects the curvature of image field, close to 0. By contrast, a concavereflective mirror corresponds to a positive lens as an optical elementfor converging light, but it is different from a positive lens in thatno chromatic aberrations occur and that the Petzval sum takes a negativevalue (a positive lens takes a positive value in this connection).

[0005] In a so called catadioptric optical system constituted bycombining a concave reflective mirror and lenses, the abovecharacteristic of the concave reflective mirror is best used to themaximum in an optical design and good correction of aberrationsbeginning with the chromatic aberrations and the curvature of imagefield are possible in spite of its simple construction. However, themanner in which an incident beam and an emergent beam are separated fora concave reflective mirror is point of greatest difficulty, and varioustechniques for this separation have been proposed.

[0006] For example, Japanese Laid-Open Application No. 8-62502 (U.S.Pat. No. 5,861,997) discloses a catadioptric optical system which is acatadioptric optical system using an exposure region (off-axis visualfield) free of an optical axis in a projection exposure apparatus and isof a type wherein intermediate images are formed twice on the way of theoptical system and the separation of beam is spatially conducted in thevicinity of the intermediate images.

SUMMARY OF THE INVENTION

[0007] The present invention is aimed at providing a catadioptricoptical system which facilitates optical adjustment and mechanicaldesign, fully corrects aberrations beginning with chromatic aberrationsand achieves a high resolution of 0.1 μm or less using a light withwavelength of 180 μm or less in the vacuum ultraviolet wavelengthregion.

[0008] Moreover, the present invention is aimed at providing aprojection exposure apparatus and an exposure method which results infacilitating optical adjustment and mechanical design, fully correctsaberrations beginning with chromatic aberrations, and ensures a highresolution of, e.g., 0.1 μm or less and lowly sets up the off-axisquantity of an effective exposure region from the optical axis.

[0009] Furthermore, the present invention is aimed at providing amanufacturing method of microdevices which results in the manufacture ofgood micro-devices at a high resolution of, e.g., 0.1 μm or less.

[0010] To achieve the previous objects, a catadioptric optical systemaccording to a first aspect of the preferred embodiment is acatadioptric optical system for forming a reduced image of a firstsurface onto a second surface and comprises a first imaging opticalsubsystem for forming a first intermediate image of the first surface,which is arranged onto an optical path between the first surface and thesecond surface and has a dioptric imaging optical system; a firstfolding mirror for deflecting a beam incident to the first intermediateimage or a beam from the first intermediate image, which is arranged inthe vicinity of a position for forming the first intermediate image; asecond imaging optical subsystem for forming a second intermediate imageof a magnification factor nearly equal to the first intermediate imagein the vicinity of a position for forming the first intermediate imagebased on the beam from the first intermediate image, which has a concavereflecting mirror and at least one negative lens; a second foldingmirror for deflecting a beam incident to the second intermediate imageor a beam from the second intermediate image, which is arranged in thevicinity of a position for forming the second intermediate image; and athird imaging optical subsystem for forming the reduced image onto thesecond surface based on a beam from the second intermediate image, whichis arranged onto an optical path between the second imaging opticalsubsystem and the second surface and has a dioptric imaging opticalsystem.

[0011] To achieve the objects, the catadioptric optical system accordingto a second aspect of the preferred embodiment is a catadioptric opticalsystem for forming a reduced image of a first surface onto a secondsurface and comprises a first imaging optical subsystem, arranged in anoptical path between the first surface and the second surface, having afirst optical axis, and a dioptric imaging optical system; a secondimaging optical subsystem, arranged in an optical path between the firstimaging optical system and the second surface, having a concavereflecting mirror and a second optical axis; and a third imaging opticalsubsystem, arranged in an optical path between the second iamgingoptical system and the second surface, having a third optical axis and adioptric imaging optical system where the first optical axis and thesecond optical axis intersect with each other, and the second opticalaxis and the third optical axis intersect with each other.

[0012] To achieve the objects, a catadioptric optical system accordingto a third aspect of the preferred embodiment is a catadioptric opticalsystem for forming a reduced image of a first surface onto a secondsurface and comprises a first imaging optical subsystem, arranged in anoptical path between the first surface and the second surface, having afirst optical axis, and a dioptric imaging optical system; a secondimaging optical subsystem, arranged in an optical path between the firstimaging optical subsystem and the second surface, having a concavereflecting mirror and a second optical axis; and a third imaging opticalsubsystem, arranged in an optical path between the second imagingoptical subsystem and the second surface, having a third optical axis,and a dioptric imaging optical system; where the first optical axis andthe third optical axis are located on a common axis.

[0013] To achieve the previous objects, a projection exposure apparatusaccording to a fourth aspect of the preferred embodiment comprises: aprojection optical system in which a pattern on a negative platearranged in the first surface is projected onto a workpiece arranged inthe second surface and exposed, which is arranged in an optical pathbetween the first surface and the second surface and the projectionoptical system comprises a first imaging optical subsystem which has adioptric imaging optical system; a second imaging optical subsystemwhich has a concave reflecting mirror; a third imaging optical subsystemwhich has a dioptric imaging optical system; a first folding mirrorwhich is arranged in an optical path between the first imaging opticalsubsystem and the second imaging optical subsystem; a second foldingmirror which is arranged in an optical path between the second imagingoptical subsystem and the third imaging optical subsystem; where thefirst imaging optical subsystem forms a first intermediate image on anoptical path between the first imaging optical subsystem and the secondimaging optical subsystem and the second imaging optical subsystem formsa second intermediate image on an optical path between the secondimaging optical subsystem and the third imaging optical subsystem.

[0014] To achieve the previous mentioned objects, an exposure methodaccording to a fifth aspect of the preferred embodiment is an exposuremethod in which a pattern on a negative plate is projected onto aworkpiece via a projection optical system and exposed and comprises thefollowing steps: an illuminating light of ultraviolet region is led tothe pattern on the negative plate; the illuminating light is led to thefirst imaging optical subsystem having a dioptric imaging optical systemvia the pattern to form a first intermediate image of the pattern on theprojection negative plate; a light from the first intermediate image isled to a second imaging optical subsystem having a concave reflectingmirror to form a second intermediate image; a light from the secondintermediate image is led to a third imaging optical subsystem having adioptric imaging optical system to form a fmal image on the workpiece; alight from the first imaging optical subsystem is deflected by a firstfolding mirror arranged on an optical path between the firstintermediate image and the second imaging optical subsystem; and a lightfrom the second imaging optical subsystem is deflected by a secondfolding mirror arranged on an optical path between the secondintermediate image and the third imaging optical subsystem.

[0015] To achieve the previous mentioned objects, an imaging opticalsystem according to a sixth aspect of the preferred embodiment is animaging optical system for forming an image of a first surface onto asecond surface and comprises at least one reflecting surface arrangedbetween the first surface and the second surface, and the reflectingsurface comprises a metallic reflecting film and a correction filmarranged on the metallic reflecting film for correcting a phasedifference which is caused by a difference in polarized state possessedby a reflected light from the metallic reflecting film.

[0016] To achieve the previous objects, a projection exposure apparatusaccording to a seventh aspect of the preferred embodiment is aprojection exposure apparatus in which a pattern on a negative platearranged on a first surface is projected onto a workpiece arranged onthe second surface and exposed and comprises that the projection opticalsystem arranged in an optical path between the first surface and thesecond surface and having at least one reflecting members and thereflecting member reflect a light so that a phase difference of a Ppolarized component and a S polarized component substantially does notexist when the P polarized component and the S polarized component cometo the photosensitive substrate.

BRIEF DESCRIPTION OF DRAWINGS

[0017]FIG. 1 is a diagram illustrating the basic construction of acatadioptric optical system of the present invention.

[0018]FIG. 2 is a diagram schematically illustrating the generalconstruction of a projection exposure apparatus provided withcatadioptric optical systems according to embodiments of the presentinvention as a projection optical system.

[0019]FIG. 3 is a diagram illustrating the positional relation between arectangular exposure region (i.e., effective exposure region) formed ona wafer W and a reference optical axis.

[0020]FIG. 4 is a diagram illustrating the lens construction of acatadioptric optical system (projection optical system PL) according toa first embodiment.

[0021]FIG. 5 is a diagram illustrating the lateral aberrations in thefirst embodiment.

[0022]FIG. 6 is a diagram for illustrating the lens construction of acatadioptric optical system (projection optical system PL) according toa second embodiment.

[0023]FIG. 7 is a diagram illustrating the lateral aberrations in thesecond embodiment.

[0024]FIG. 8 is a diagram illustrating the general construction of theprojection exposure apparatus of the embodiment shown in FIG. 2.

[0025]FIG. 9 is an enlarged view illustrating a part related to anilluminating optical system which constitutes a part of the projectionexposure apparatus of FIG. 8.

[0026]FIG. 10 is an enlarged view illustrating a part related to anilluminating optical system which constitutes a part of the projectionexposure apparatus of FIG. 8.

[0027]FIG. 11 is a diagram illustrating a flowchart of a manufacturingexample of devices (semiconductor chip such as IC or LSI and the like,liquid crystal panel, CCD, thin-film magnetic head, micro-machine and soon).

[0028]FIG. 12 is a drawing for illustrating one example of detailed flowof step 204 of FIG. 11 in the case of a semiconductor device.

[0029]FIG. 13A is a diagram illustrating the lens construction of acatadioptric optical system (projection optical system PL) according toa third embodiment.

[0030]FIG. 13B is a diagram for illustrating principal parts of acatadioptric optical system (projection optical system PL) according toa third embodiment.

[0031]FIG. 14 is a diagram illustrating the lateral aberrations in thethird embodiment.

[0032]FIG. 15 is a diagram illustrating the construction of modificationexample 1 of the third embodiment.

[0033]FIG. 16 is a diagram illustrating the construction of modificationexample 2 of the third embodiment.

[0034]FIG. 17 is a diagram illustrating the construction of modificationexample 3 of the third embodiment.

[0035]FIG. 18 is a diagram illustrating the construction of modificationexample 4 of the third embodiment.

[0036]FIG. 19 is a drawing illustrating the construction of modificationexample 5 of the third embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0037]FIG. 1 is a diagram illustrating the basic construction of acatadioptric optical system of the present invention. In the diagram,the catadioptric optical system of the present invention is applied tothe projection optical system of a projection exposure apparatus.

[0038] As shown in FIG. 1, the catadioptric optical system of thepresent invention is provided with a dioptric type first imaging opticalsystem G1 for forming a first intermediate image of a pattern of reticleR arranged as a first surface as a negative plate.

[0039] A first optical path folding mirror 1 is arranged in the vicinityof formation position of the first intermediate image formed by thefirst imaging optical system G1. The first optical path folding mirror 1deflects a beam incident to the first intermediate image or a beam fromthe first intermediate image to a second imaging optical system G2. Thesecond imaging optical system G2 has a concave reflecting mirror (CM)and at least one negative lens 3, and a second intermediate image (animage of the first intermediate image and a secondary image of thepattern) nearly equal in size to the first intermediate image is formedin the vicinity of formation position of the first intermediate imagebased on the beam from the first intermediate image.

[0040] A second optical path folding mirror 2 is arranged in thevicinity of formation position of the second intermediate image formedby the second imaging optical system G2. The second optical path foldingmirror 2 deflects a beam incident to the second intermediate image or abeam from the second intermediate image to a dioptric type third imagingoptical system G3. Here, the reflecting surface of the first opticalpath folding mirror 1 and the reflecting surface of the second opticalpath folding mirror 2 are positioned so as not to overlap spatially. Thethird imaging optical system G3 forms a reduced image of pattern of thereticle (an image of the second intermediate image and a final image ofthe catadioptric optical system) on a wafer W arranged as a secondsurface as photosensitive substrate based on the beam from the secondintermediate image.

[0041] In the above construction, a chromatic aberration and a positivePetzval sum produced by the first imaging optical system GI and thethird imaging optical system G3, which are dioptric optical systemscomprising plural lenses, are compensated by the concave reflectingmirror CM and the negative lens(es) 3. Moreover, the second intermediateimage can be formed in the vicinity of the first intermediate image by aconstruction that the second imaging optical system G2 has a nearlyequal (unit) magnification. In the present invention, the distance fromthe optical axis of an exposure region (i.e., an effective exposureregion), namely, the off-axis quantity can be lowly set up by conductingan optical path separation in the vicinity of these two intermediateimages. This is not only favorable in aberration correction, but alsofavorable in miniaturization of optical systems, optical adjustment,mechanical design, manufacturing cost, and so on.

[0042] As described above, the second imaging optical system G2 bearsthe compensation of the chromatic aberration and the positive Petzvalsum produced by the first imaging optical system GI and the thirdimaging optical system G3 all alone. For this reason, a large power(dioptric power) must be set up for both the concave reflecting mirrorCM and the negative lens(es) 3 constituting the second imaging opticalsystem G2. Therefore, if the symmetry of the second imaging opticalsystem G2 collapses, the occurrence of asymmetrical chromaticaberrations such as lateral chromatic aberration or chromatic comaaberration increases, thus an enough resolution power cannot beobtained. Accordingly, the present invention succeeds in ensuring goodsymmetry and preventing the previous mentioned asymmetrical chromaticaberrations by adopting a construction which results in a set up havinga nearly unity magnification for the second imaging optical system G2and by arranging the concave reflecting mirror CM in the vicinity of itspupil position.

[0043] The construction of the present invention is described in moredetail hereafter with reference to the following conditions.

[0044] In the present invention, it is preferable that the magnificationβ2 satisfies the following condition (1).

0.82<|β2 |<1.20  (1)

[0045] Condition (1) specifies an appropriate range of magnification β2of the second imaging optical system G2.

[0046] If this condition (1) is not satisfied, it is not preferredbecause the off-axis quantity for the optical path separation increases,thus the large scale and complication of the optical systems cannot beavoided. In addition, it is not preferred because the occurrence ofasymmetrical chromatic aberrations such as lateral chromatic aberrationor chromatic coma aberration and the like cannot be prevented.

[0047] It is more preferable that the lower limit is 0.85 and the upperlimit is 1.15 for condition (1). It is even more preferable that thelower limit is 0.87 for condition (1).

[0048] In the present invention, it is preferable that the followingcondition (2) is satisfied.

|L1−L2|/|L1|<0.15  (2)

[0049] Here, L1 is the distance between the first intermediate image andthe concave reflecting mirror CM in the second imaging optical system G2along the optical axis. L2 is the distance between the secondintermediate image and the concave reflecting mirror CM in the secondimaging optical system G2 along the optical axis. In the case of thepresent invention, L1 and L2 are distances from the intersection of theoptical axis and a perpendicular from the intermediate image to theoptical axis when extending the perpendicular down to the concavereflecting mirror CM along the optical axis because the intermediateimage is not formed on the optical axis.

[0050] Condition (2) specifies a positional relation between the firstintermediate image formed by the first imaging optical system G1 and thesecond intermediate image formed by the second imaging optical systemG2.

[0051] If condition (1) is not satisfied, it is not preferred becausethe off-axis quantity for the optical path separation increases, thusthe large scale and complication of the optical systems cannot beavoided.

[0052] It is more preferable that the upper limit is 0.85 for condition(2).

[0053] In the present invention, it is preferable that the firstintermediate image is formed on the optical path between the firstoptical path folding mirror 1 and the second imaging optical system G2,and the second intermediate image is formed on the optical path betweenthe second imaging optical system G2 and the second optical path foldingmirror 2. In this case, the stability of the optical systems increasesand the optical adjustment and mechanical design become easy because thedistance between first surface and second surface can be shortened.Moreover, when the present invention is applied to a projection exposureapparatus, the height of the whole apparatus can be reduced because thedistance between the reticle R arranged on the first surface and thewafer arranged on second surface is shortened.

[0054] In the present invention, it is preferable that the followingcondition (3) is satisfied.

0.20<|β|/|β1|<0.50  (3)

[0055] Here, β is the magnification of the catadioptric optical system(projection optical system if applied to a projection exposureapparatus). β1 is the magnification of the first imaging optical systemG1.

[0056] Condition (3) specifies an appropriate range of the ratio of themagnification of the whole system β to the magnification of the firstimaging optical system G1.

[0057] If the ratio is more than the upper limit of condition (3), it isundesirable because the angle of dispersion (angle range) of a beamincident into the first optical path folding mirror 1 and the secondoptical path folding mirror 2 increases and consequently the design of areflecting film becomes difficult. In particular, reflecting filmmaterials usable for a light with wavelength shorter than 180 nm arealso limited, thus it is difficult to keep the reflectivity at a highlevel in a broad angular band constant. The difference in reflectivitybetween P polarized light and S polarized light or the phase change alsochanges with the angle of incidence and therefore in its turn isassociated with deterioration of the imaging property of the wholesystem.

[0058] On the other hand, if the ratio is less than the lower limit ofthis condition (3), it is undesirable because the load of magnificationfactor, which should be the burden of the third imaging optical systemG3, rises, and thus a large scale of the optical systems cannot beavoided.

[0059] Moreover, it is more preferable that the lower limit of condition(3) is 0.25 and its upper limit is 0.46.

[0060] Furthermore, in the present invention, it is preferable that thecatadioptric optical system is a telecentric optical system on bothsides of the first surface and the second surface. When the system isapplied to a projection exposure apparatus, it is preferable that theprojection optical system is a telecentric optical system on bothreticle side and wafer side. This construction enables to lowly suppressthe magnification error or distortion of image when positional errors orwarp of the reticle or wafer and the like occur. Furthermore, it ispreferable that an angle made by a light passing through the center ofbeam (i.e., principal ray) becomes 50 minutes or less in the whole fieldso that the optical systems are substantially telecentric.

[0061] In the present invention, it is preferable to satisfy thefollowing condition (4), in addition to the catadioptric optical system,which is telecentric on both sides.

|E−D |/| E|<0.24  (4)

[0062] Here, E is the distance between the surface on the image side ofthe first imaging optical system G1 and its exit pupil position alongthe optical axis. D is the distance by air conversion from the surfaceon the image side of the first imaging optical system G1 to the concavereflecting mirror CM in the second imaging optical system G2 along theoptical axis.

[0063] Condition (4) specifies a positional relation between the exitpupil of the first imaging optical system G1 and the concave reflectingmirror CM.

[0064] If condition (4) is not satisfied, it is not preferable becausethe occurrence of asymmetrical chromatic aberrations such as lateralchromatic aberration or chromatic coma aberration and the like cannot belowly suppressed.

[0065] Moreover, it is more preferable that the upper limit of condition(4) is 0.17.

[0066] Furthermore, it is preferable in the present invention that theintersection line of an assumed extension plane of the reflecting plane(an assumed plane obtained by infinitely extending a planar reflectingplane) of the first optical path folding mirror 1 and an assumedextension plane of the reflecting plane of the second optical pathfolding mirror 2 is so set up that an optical axis AX1 of the firstimaging optical system G1, an optical axis AX2 of the second imagingoptical system G2 and an optical axis AX3 of the third imaging opticalsystem G3 intersect at one point (reference point). This constructionresults in the optical axis AX1 of the first imaging optical system G1and the optical axis AX3 of the third imaging optical system G3 becominga common optical axis, and particularly enables to position the threeoptical axes AX1-AX3 and the two reflecting planes in relation to onereference point. Therefore, the stability of the optical systemsincreases, and the optical adjustment and mechanical design become easy.An even higher accuracy optical adjustment can be facilitated and evenhigher stability can be achieved by setting the optical systems so thatthe optical axis AX2 is perpendicular to the optical axis AX1 of thefirst imaging optical system G1 and the optical axis AX3 of the thirdimaging optical system G3.

[0067] Furthermore, it is preferable in the present invention that alllenses constituting the first imaging optical system G1 and all lensesconstituting the third imaging optical system G3 are arranged along asingle optical axis. This construction causes any fiexure due to gravityto become rotationally symmetrical and provides to lowly suppress thedeterioration of imaging property due to the optical adjustment. Inparticular, when it is applied to a projection exposure apparatus, thereticle R and the wafer W can be arranged parallel to each other along aplane perpendicular to the gravity direction (i.e., horizontal plane)and all lenses constituting the first imaging optical system G1 and thethird imaging optical system G3 can be arranged horizontally along asingle optical axis in the gravity direction by using the first imagingoptical system G1 and the third imaging optical system G3 in an uprightposition along the common optical axis. As a result, the reticle, waferand most of the lenses constituting the projection optical system areheld horizontally, not subjected to an asymmetrical deformation due totheir own weight, and this is very favorable in ensuring opticaladjustment, mechanical design, high resolution and the like.

[0068] Further, it is preferable in the present invention that over 85%of the number of lenses in all lenses constituting the catadioptricoptical system (the projection optical system in the case of applying itto a projection exposure apparatus) are arranged along a single opticalaxis. For example, if the first imaging optical system G1 and the thirdimaging optical system G3 are used in an upright position along thecommon optical axis, almost all lenses in many lenses constituting theoptical systems are held horizontally and an asymmetrical deformationdue to their own weight does not occur by this construction, thereforeit is further favorable in ensuring optical adjustment, mechanicaldesign, high resolution and the like.

[0069] Additionally, as described above, the negative lens(es) 3 in thesecond imaging optical system G2 requires a large power (refractivepower) to compensate for chromatic aberrations being produced by thefirst imaging optical system G1 and the third imaging optical system G3alone. Accordingly, it is preferable in the present invention that thesecond imaging optical system G2 has at least two negative lenses 3.This construction enables to divide and bear a necessary power with atleast two negative lenses and in its turn provides to constitutestabilized optical systems.

[0070] Embodiments of the present invention are described hereafter,with reference to the following drawings.

[0071]FIG. 2 is a diagram schematically showing the general constructionof a projection exposure apparatus which is provided with a catadioptricoptical system according to embodiments of the present invention as aprojection optical system. In FIG. 2, the Z axis is set up in parallelto a reference optical axis AX of the catadioptric optical systemconstituting a projection optical system PL, the Y axis is set up inparallel to the paper surface of FIG. 2 in a plane perpendicular to theoptical axis AX. Moreover, FIG. 2 schematically shows the generalconstruction of a projection exposure apparatus, and its detailedconstruction will be described later in FIGS. 8-10.

[0072] The described projection exposure apparatus is provided with,e.g., a F₂ laser (wavelength 157.624 nm) as a light source 100 forsupplying an illuminating light of ultraviolet region. The illuminatinglight emergent from the light source 100 evenly illuminates a reticle Rwhere a given pattern is formed.

[0073] Moreover, an optical path between the light source 100 and anilluminating optical system IL is sealed by a casing (not shown), and aspace from the light source 100 to an optical member on the reticle sidein the illuminating optical system IL is filled with an inert gas, suchas helium gas or nitrogen gas and the like being a gas with a lowabsorptivity of exposure light, or kept in a nearly vacuum state.

[0074] The reticle R is in parallel held in the XY plane on a reticlestage RS via a reticle holder RH. A pattern to be transferred is formedon the reticle, and a rectangular (slit-like) pattern region with a longside along the X direction and a short side along the Y direction in thewhole pattern region is illuminated. The reticle stage RS is movabletwo-dimensionally along the reticle surface (i.e., the XY plane) by theaction of a driving system whose illustration is omitted and is soconstituted that its position coordinates are measured and positionallycontrolled by an interferometer RIF using a reticle moving (measuring)mirror RM.

[0075] A light from the pattern formed on the reticle forms a reticlepattern image on a wafer W, which is a photosensitive substrate, via acatadioptric type projection optical system PL. The wafer W is inparallel held on the XY plane on a wafer stage WS via a wafer table(wafer holder) WT. Then, a pattern image is formed in a rectangularexposure region with a long side along the X direction and a short sidealong the Y direction on the wafer W so as to correspond to therectangular illuminating region on the reticle R optically. The waferstage WS is movable two-dimensionally along the wafer surface (i.e., theXY plane) by the action of a driving system whose illustration isomitted, and its position coordinates are measured and positionallycontrolled by an interferometer WIF using a wafer moving (measuring)mirror WM.

[0076]FIG. 3 is a diagram showing a positional relation between therectangular exposure region (i.e., effective exposure region) formed onthe wafer W and the reference optical axis.

[0077] As shown in FIG. 3, in the embodiments, a rectangular effectiveexposure region ER having a desirable size is set up in a positionseparated from the reference axis AX by only an off-axis quantity A inthe +Y direction in a circular region (image circle) with a radius B andwith the reference axis AX as its center. Here, the X-direction lengthof the effective exposure region ER is LX and its Y-direction length isLY.

[0078] In other words, in the embodiments, the rectangular effectiveexposure region ER having a desirable size is set up in a positionseparated from the reference axis AX by an off-axis quantity A in the +Ydirection, and the radius B of the circular image circle IF is specifiedso as to include the effective exposure region ER with the referenceaxis AX as its center.

[0079] Therefore, a description is omitted, but a rectangularillumination region (i.e., effective illumination region) with a sizeand a shape corresponding to the effective exposure region ER is formedin a position separated from the reference axis AX by only a distancecorresponding to the off-axis quantity A in the −Y direction.

[0080] Moreover, in the described projection exposure apparatus, theprojection optical system PL is so constituted that its inside is keptin an air (gas)-tight state between an optical member arranged on thereticle side (lens L11 in the embodiments) and an optical memberarranged on the wafer side (lens L311 in the embodiments) among opticalmembers constituting the projection optical system PL, and is filledwith an inert gas such as helium gas or nitrogen gas and the like orkept in a nearly vacuum state.

[0081] Furthermore, the reticle R and the reticle stage RS and the likeare arranged in a narrow optical path between the illumination opticalsystem IL and the projection optical system PL, but an inert gas, suchas nitrogen or helium gas and the like, is filled into a casing (notshown) which seals and encloses the reticle R and the reticle stage RSand the like or the casing is kept in a nearly vacuum state.

[0082] Additionally, the wafer W and the wafer stage WS and the like arearranged in a narrow optical path between the projection optical systemPL and the wafer W, but an inert gas, such as nitrogen or helium gas andthe like, is filled into a casing (not shown) which seals and enclosesthe wafer W and the wafer stage WS and the like or the casing is kept ina nearly vacuum state.

[0083] Thus, an atmosphere in which the exposure light is almost notabsorbed is formed over the whole optical path from the light source 100to the wafer W.

[0084] As described above, the illumination region on the reticle andthe exposure region on the wafer W (i.e., effective exposure region ER)specified by the projection optical system PL are rectangles with shortsides in the Y direction. Therefore, the reticle pattern is scanned andexposed for a region which has a width equal to the long side of theexposure region on the wafer W and has a length corresponding to thescan quantity (moving quantity) of the wafer W by moving (scanning) thereticle stage RS and the wafer stage WS and in its turn the reticle Rand the wafer W synchronously in the same direction (i.e., sameorientation) along the short-side direction, i.e., the Y direction ofthe rectangular exposure region and the illumination region, while thepositional control of the reticle R and the wafer W is taken by adriving system or an interferometer (RIF, WIF) and the like.

[0085] In the embodiments, the projection optical system PL includingthe catadioptric optical system is provided with a dioptric type firstimaging optical system G1 for forming a first intermediate image of thepattern of the reticle arranged on the first surface, a second imagingoptical system G2 comprising a concave reflecting mirror CM and twonegative lenses 3 for forming a second intermediate image nearly unitaryto the first intermediate image (a nearly equal size image of the firstintermediate image and a secondary image of the reticle pattern) and adioptric type third imaging optical system G3 for forming a final imageof the reticle pattern (a reduced image of the reticle pattern) on thewafer W arranged on the second surface based on a light from the secondintermediate image.

[0086] Moreover, in the embodiments, a first optical path folding mirror1 for deflecting the light from the first imaging optical system G1 tothe second imaging optical system G2 is arranged in the vicinity of theformation position of the first intermediate image in an optical pathbetween the first imaging optical system G1 and the second imagingoptical system G2. A second optical path folding mirror 2 for deflectingthe light from the second imaging optical system G2 to the third imagingoptical system G3 is arranged in the vicinity of the formation positionof the second intermediate image in an optical path between the secondimaging optical system G2 and the second imaging optical system G3. Inthe embodiments, the first intermediate image and the secondintermediate image are formed in an optical path between the firstoptical path folding mirror 1 and the second imaging optical system G2and an optical path between the second imaging optical system G2 and thesecond optical path folding mirror 2, respectively.

[0087] Furthermore, in the embodiments, the first imaging optical systemG1 has a linearly extended optical axis AX1, the third imaging opticalsystem G3 has a linearly extended optical axis AX3, the optical axis AX1and the optical axis AX3 are set up so as to coincide with the referenceoptical axis AX, which is a common single axis. As a result, the reticleand the wafer W are arranged in parallel to each other along a planeperpendicular to the gravity direction, i.e., a horizontal plane. Inaddition, all lenses constituting the first imaging optical system G1and all lenses constituting the third imaging optical system G3 are alsoarranged along the horizontal plane on the reference optical axis AX.

[0088] On the other hand, the second imaging optical system G2 also hasa linearly extended optical axis AX2, and this optical axis AX2 is setup so as to be perpendicular to the reference optical axis AX, which isthe common single axis. Moreover, both the first optical path foldingmirror 1 and the second optical path folding mirror 2 have planarreflecting surfaces and are integrally constituted as one optical member(one optical path folding mirror FM) with two reflecting planes. Theintersection line of these two reflecting planes (strictly theintersection line of their assumed extended planes) are set up so thatthe axis AX1 of the first imaging optical system G1, the axis AX2 of thesecond imaging optical system G2 and the axis AX3 of the third imagingoptical system G3 intersect at one point. Furthermore, both the firstoptical path folding mirror 1 and the second optical path folding mirror2 are constituted as front surface reflecting mirrors in the firstembodiment and in the second embodiment, and both the first optical pathfolding mirror 1 and the second optical path folding mirror 2 areconstituted as rear (back) surface reflecting mirrors in the thirdembodiment. The smaller the interval between the effective region ofreflecting plane of the optical path folding mirror FM and optical AX isset up, the less the off-axis quantity A of the effective exposureregion will be.

[0089] In the embodiments, fluorite (CaF₂ crystal) is used for alldioptric optical members (lens component) constituting the projectionoptical system. The wavelength of the F₂ laser being exposure light is157.624 nm, the dioptric index of CaF₂ in the vicinity of 157.624 nmchanges in aratio of −2.6×10⁻⁶ per +1 pm of wavelength change and in aratio of +2.6×10⁻⁶ per −1 pm of wavelength change. In other words, thedispersion of dioptric index (dn/dλ) of CaF₂ on the vicinity of 157.624nm is 2.6×10⁻⁶ pm.

[0090] Therefore, in the first and second embodiments, the dioptricindex of CaF₂ to the wavelength 157.624 nm is 1.559238, the dioptricindex of CaF₂ to 157.624 nm +1 pm =157.625 nm is 1.5592354, and thedioptric index of CaF₂ to 157.624 nm −1 pm =157.623 nm is 1.5592406. Onthe other hand, in the third embodiment, the dioptric index of CaF₂ tothe wavelength 157.624 nm is 1.559307, the dioptric index of CaF₂ to157.624 nm +1 pm 157.625 nm is 1.5593041, and the dioptric index of CaF₂to 157.624 nm −1 pm=157.623 nm is 1.5593093.

[0091] Furthermore, in the embodiments, if the height in a directionperpendicular to the optical axis is taken as y, the distance (amount ofsag) from a tangent plane at the vertex of aspherical surface to aposition on the aspherical surface at the height y along the opticalaxis as z, the vertex curvature radius as r, the conic coefficient as kand the n-order aspherical coefficient as C_(n), then the asphericalsurface is expressed by the following numerical formula (a).

z=(y ² /r)/[l+{ l−(l+k)·y ² /r ²}^(½) ]+C ₄ ·y ⁴ +C ₆ ·y ⁶ +C ₈ ·y ⁸ +C₁₀ ·y ¹⁰ +C ₁₂ ·y ¹² +C ₁₄ ·y ¹⁴  (a)

[0092] In the embodiments, a * sign is attached on the right side ofsurface no. on a lens surface which is formed into an aspherical shape.

[0093] Embodiment 1

[0094]FIG. 4 is a diagram showing the lens construction of acatadioptric optical system (projection optical system PL) according toa first embodiment. In the first embodiment, the present invention isapplied to a projection optical system in which aberrations includingchromatic aberrations are corrected for an exposure light withwavelength of 157.624 nm ±1 pm.

[0095] In the catadioptric optical system of FIG. 4, the first imagingoptical system G1 comprises a negative meniscus lens L11 having anaspherical concave surface facing to the wafer side, a biconvex lensL12, a biconvex lens L13, a biconvex lens L14, a negative meniscus lensL15 having a convex surface facing to the reticle side, a positivemeniscus lens L16 having a concave surface facing to the reticle side, apositive meniscus lens L17 having a concave surface facing to thereticle side, a positive meniscus lens L18 having a concave surfacefacing to the reticle side, a biconvex lens L19 and a positive meniscuslens L110 having a convex surface facing to the reticle side in orderfrom the reticle side.

[0096] The second imaging optical system G2 comprises a negativemeniscus lens L21 having a concave surface facing to the reticle side, anegative meniscus lens L22 having an aspherical concave surface facingto the reticle side and a concave reflecting mirror CM in order from thereticle side along the propagative route of light (i.e., the incidentside).

[0097] The third imaging optical system G3 comprises a biconvex lens L31having an aspherical convex surface facing to the facing reticle side, abiconvex lens L32, a biconvex lens L33, a biconcave lens L34, a positivemeniscus lens L35 having a convex surface facing to the reticle side, anaperture stop AS, a biconvex lens L36 having an aspherical convexsurface facing to the wafer side, a biconvex lens L37, a positivemeniscus lens L38 having a convex surface facing to the reticle side, apositive meniscus lens L39 having a convex surface facing to the reticleside, a biconcave lens L310 and a plano-convex lens L311 having a planesurface facing to the wafer side in order from the reticle side alongthe propagative route of light.

[0098] Values of data of the catadioptric optical system of the firstembodiment are identified in the following table (1). In the table (1),λ represents the wavelength of exposure light, β the projectionmagnification (magnification of whole system), NA the numerical apertureon the image side (wafer side), B the radius of image circle IF on waferW, A the off-axis quantity of effective exposure region ER, LX thedimension of effective exposure region ER along the X direction(dimension of long side), and LY the dimension of effective exposureregion ER along the Y direction (dimension of short side), respectively.

[0099] Moreover, the surface no. represents the order of surfaces fromthe reticle side along the propagative direction of light from thereticle surface, being the object surface (first surface) to the wafersurface, being the image surface (second surface), r the curvatureradius of surface (vertex curvature radius in the case of asphericalsurface: mm), d the axial space of surface, i.e., surface distance (mm),and n the dioptric index to wavelength, respectively.

[0100] Furthermore, the surface distance d changes its sign withreflected degree. Therefore, the sign of the surface distance d is takenas negative on the optical path from the first optical path foldingmirror 1 to the concave reflecting mirror CM and on the optical pathfrom the second optical path folding mirror 2 to the image surface, andis taken as positive in other optical paths. Then, the curvature radiusof a convex surface facing to the reticle side is taken as positive andthe curvature radius of a concave surface facing to the reticle side istaken as negative in the first imaging optical system G1. On the otherhand, the curvature radius of a concave surface facing to the reticleside is taken as positive and the curvature radius of a convex surfacefacing to the reticle side is taken as negative in the third imagingoptical system G3. The curvature radius of a concave surface facing tothe reticle side (i.e., incident side) is taken as positive and thecurvature radius of a convex surface facing to the reticle side (i.e.,incident side) is taken as negative along the progression route of lightin the second imaging optical system G2. TABLE 1 (Main data) λ = 157.624nm β = −0.25 NA = 0.75 B = 14.6 mm A = 3 mm LX = 22 mm LY = 6.6 mm (Dataof optical members) Surface no. r d n (reticle surface) 129.131192  18233.14221 20.000000 1.559238 (lens L11)  2* 229.43210 8.970677  3286.74048 31.000034 1.559238 (lens L12)  4 −803.12188 1.000000  5666.75874 33.633015 1.559238 (lens L13)  6 −296.74142 1.000000  7180.00000 38.351830 1.559238 (lens L14)  8 −2028.08028 13.262240  9201.14945 12.933978 1.559238 (lens L15) 10 128.43682 221.621142  11*−127.65364 20.866949 1.559238 (lens L16) 12 −120.00000 1.000000 13−302.13109 23.424817 1.559238 (lens L17) 14 −150.00000 1.000000 15−1158.54680 23.049991 1.559238 (lens L18) 16 −228.52501 1.000000 17433.60390 22.934308 1.559238 (lens L19) 18 −656.20038 1.000000 19188.30389 21.335899 1.559238 (lens L110) 20 563.10068 86.000000 21 ∞−273.261089 (first optical path folding mirror 1) 22 114.73897−12.000000 1.559238 (lens L21) 23 453.07648 −16.355803  24* 172.15013−13.328549 1.559238 (lens L22) 25 395.88538 −28.227312 26 162.8584428.227312 (concave reflecting mirror CM) 27 395.88538 −13.3285491.559238 (lens L22)  28* 172.15013 16.355803 29 453.07648 12.0000001.559238 (lens L21) 30 114.73897 273.261089 31 ∞ −94.835481 (secondoptical path folding mirror 2)  32* −774.94652 −26.931959 1.559238 (lensL31) 33 275.96516 −1.000000 34 −376.08486 −31.371246 1.559238 (lens L32)35 388.08658 −1.000000 36 −219.25460 −29.195314 1.559238 (lens L33) 374359.72825 −32.809802 38 505.14516 −12.000000 1.559238 (lens L34) 39−128.75641 −209.396172 40 −180.58054 −24.481519 1.559238 (lens L35) 41−331.81286 −14.336339 42 ∞ −30.366910 (aperture stop AS) 43 −1502.56896−24.392042 1.559238 (lens L36)  44* 933.76923 −1.000000 45 −357.34412−25.686455 1.559238 (lens L37) 46 2099.98513 −1.000000 47 163.08575−32.557214 1.559238 (lens L38) 48 −631.02443 −1.000000 49 −124.04732−35.304921 1.559238 (lens L39) 50 −639.72650 −18.536315 51 467.75212−40.196625 1.559238 (lens L310) 52 −616.22436 −1.000000 53 −95.47627−38.068687 1.559238 (lens L311) 54 ∞ −11.016920 (wafer surface)(Aspherical data) Surface 2 r = 229.43210 κ = 0.000000 C₄ = 0.174882 ×10⁻⁷ C₆ = −0.593217 × 10⁻¹² C₈ = −0.194756 × 10⁻¹⁶ C₁₀ = 0.677479 ×10⁻²¹ C₁₂ = −0.212612 × 10⁻²⁵ C₁₄ = −0.320584 × 10⁻³⁰ Surface 11 r =−127.65364 κ = 0.000000 C₄ = −0.130822 × 10⁻⁷ C₆ = 0.512133 × 10⁻¹² C₈ =0.875810 × 10⁻¹⁶ C₁₀ = 0.138750 × 10⁻¹⁹ C₁₂ = −0.203194 × 10⁻²⁵ C₁₄ =0.241236 × 10⁻²⁷ Surface 24 and Surface 28 (same Surface) r = 172.15013κ = 0.000000 C₄ = 0.293460 × 10⁻⁷ C₆ = −0.868472 × 10⁻¹² C₈ = −0.848590× 10⁻¹⁷ C₁₀ = −0.159330 × 10⁻²² C₁₂ = 0.868714 × 10⁻²⁶ C₁₄ = −0.116970 ×10⁻²⁹ Surface 32 r = −774.94652 κ = 0.000000 C₄ = 0.253400 × 10⁻⁷ C₆ =−0.505553 × 10⁻¹² C₈ = 0.151509 × 10⁻¹⁶ C₁₀ = −0.433597 × 10⁻²¹ C₁₂ =0.841427 × 10⁻²⁶ C₁₄ = 0.165932 × 10⁻³⁰ Surface 44 r = 933.76923 κ =0.000000 C₄ = −0.140105 × 10⁻⁷ C₆ = −0.779968 × 10⁻¹² C₈ = −0.148693 ×10⁻¹⁶ C₁₀ = 0.100788 × 10⁻²¹ C₁₂ = −0.251962 × 10⁻²⁵ C₁₄ = 0.104216 ×10⁻²⁹ (Corresponding values of conditions) β1 = −0.626 β2 = −0.919 β3 =−0.435 L1 = 335.3 mm L2 = 310.0 mm E = 484.8 mm D = 443.3 mm (1) |β2| =0.919 (2) |L1 − L2| / |L1| = 0.076 (3) |β| / |β1| = 0.400 (4) |E − D| /|E| = 0.086

[0101]FIG. 5 are charts showing the lateral aberrations in the firstembodiment.

[0102] In the aberration charts, Y represents the image height, solidlines the wavelength 157.624 nm, broken lines 157.624 +1 pm =157.625 nmand dashed lines 157.624 −1 pm =157.623 nm, respectively.

[0103] As is evident from the aberration charts, it is generally knownthat the chromatic aberrations are well corrected for the exposure lightwith a wavelength of 157.624 ±1 pm in the first embodiment.

[0104] Embodiment 2

[0105]FIG. 6 is a diagram showing the lens construction of acatadioptric optical system (projection optical system PL) according tothe second embodiment. In the second embodiment, this invention isapplied to a projection optical system in which aberrations includingchromatic aberrations are corrected for an exposure light withwavelength width of 157.624 nm ±1 pm similarly as in the firstembodiment.

[0106] In the catadioptric optical system of FIG. 6, the first imagingoptical system G1 comprises a positive meniscus lens L11 having anaspherical concave surface facing the wafer side, a negative meniscuslens L12 having a concave surface facing the reticle side, a biconvexlens L13, a biconvex lens L14, a positive meniscus lens L15 having aconvex surface facing the reticle side, a positive meniscus lens L16having an aspherical concave surface facing the reticle side, a positivemeniscus lens L17 having a concave surface facing the reticle side, apositive meniscus lens L18 having a concave surface facing the reticleside, a biconvex lens L19 and a positive meniscus lens L110 having anaspherical concave surface facing the wafer side in order from thereticle side.

[0107] The second imaging optical system G2 comprises a negativemeniscus lens L21 having a concave surface facing the reticle side, anegative meniscus lens L22 having an aspherical concave surface facingthe reticle side and a concave reflecting mirror CM in order from thereticle side along the propagative route of light (i.e., the incidentside).

[0108] The third imaging optical system G3 comprises a biconvex lens L31having an aspherical convex surface facing the reticle side, a biconvexlens L32, a positive meniscus lens L33 having a convex surface facingthe reticle side, a biconcave lens L34, a biconvex lens L35, an aperturestop AS, a negative meniscus lens L36 having an aspherical convexsurface facing the wafer side, a biconvex lens L37, a positive meniscuslens L38 having an aspherical convex surface facing the reticle side, apositive meniscus lens L39 having a convex surface facing the reticleside, a biconcave lens L310 and a plano-convex lens L311 having a planesurface facing the wafer side in order from the reticle side along thepropagative route of light (i.e., the incident side).

[0109] Values of data of the catadioptric optical system of the secondembodiment are identified in the following table (2). In the table (2),λ represents the wavelength of exposure light, β the projectionmagnification (magnification of whole system), NA the numerical apertureon the image side (wafer side), B the radius of image circle IF on waferW, A the off-axis quantity of effective exposure region ER, LX thedimension of effective exposure region ER along the X direction(dimension of long side), and LY the dimension of effective exposureregion ER along the Y direction (dimension of short side), respectively.

[0110] Moreover, surface no. represents the order of surfaces from thereticle side along the propagative direction of light from the reticlesurface being the object surface (first surface) to the wafer surface,being the image surface (second surface), r the curvature radius ofsurface (vertex curvature radius in the case of aspherical surface: mm),d the axial space of surface, i.e., surface distance (mm), and n thedioptric index to wavelength, respectively.

[0111] Furthermore, the surface distance d changes its sign withreflected degree. Therefore, the sign of the surface distance d is takenas negative on the optical path from the first optical path foldingmirror 1 to the concave reflecting mirror CM and on the optical pathfrom the second optical path folding mirror 2 to the image surface, andis taken as positive in other optical paths. Then, the curvature radiusof a convex Surface facing to the reticle side is taken as positive andthe curvature radius of a concave surface facing to the reticle side istaken as negative in the first imaging optical system G1. On the otherhand, the curvature radius of a concave surface surfacing to the articleside is taken as positive and the curvature radius of a convex surfacefacing to the article side is taken as negative in the third imagingoptical system G3. The curvature adius of a concave surface facing tothe reticle side (i.e., the incident side) is taken as positive and thecurvature radius of a convex surface facing to the reticle side (i.e.,the incident side) is taken as negative along the propagative route oflight in the second imaging optical system G2. TABLE 2 (Main data) λ =157.624 nm β = −0.25 NA = 0.75 B = 14.6 mm A = 3 mm LX = 22 mm LY = 6.6mm (Data of optical members) Surface no. r d n (reticle 74.237501surface)  1 392.09887 18.011517 1.559238 (lens L11)  2* 1161.2685422.550885  3 −197.82341 12.000000 1.559238 (lens L12)  4 −320.240451.072412  5 4535.10509 27.582776 1.559238 (lens L13)  6 −230.222071.003799  7 180.02979 31.376675 1.559238 (lens L14)  8 −16797.465441.001727  9 120.09101 49.640624 1.559238 (lens L15) 10 111.81156146.176310  11* −147.64267 50.000000 1.559238 (lens L16) 12 −120.000001.034195 13 −243.75596 21.927192 1.559238 (lens L17) 14 −150.025451.001112 15 −355.46587 23.499758 1.559238 (lens L18) 16 −170.068691.005485 17 380.97487 22.758028 1.559238 (lens L19) 18 −1174.105331.018161 19 162.68954 24.816537 1.559238 (lens L110)  20* 644.6964286.000000 21 ∞ −275.440338 (first optical path folding mirror 1) 22116.98457 −20.000000 1.559238 (lens L21) 23 556.37904 −19.644110  24*165.29528 −22.001762 1.559238 (lens L22) 25 383.86012 −26.835741 26170.53370 26.835741 (concave reflect- ing mirror CM) 27 383.8601222.001762 1.559238 (lens L22)  28* 165.29528 19.644110 29 556.3709420.000000 1.559238 (lens L21) 30 116.98457 275.440338 31 ∞ −106.008415(second optical path folding mirror 2)  32* −8761.14467 −25.5359771.559238 (lens L31) 33 279.72974 −1.078193 34 −751.81935 −30.3039601.559238 (lens L32) 35 352.73770 −1.006012 36 −178.20333 −35.6752041.559238 (lens L33) 37 −1076.81270 −51.479106 38 1804.27479 −28.7465351.559238 (lens L34) 39 −120.27525 −169.573423 40 −250.01576 −35.5359411.559238 (lens L35) 41 521.40215 −35.714360 42 ∞ −24.295048 (aperturestop AS) 43 152.18493 −24.773335 1.559238 (lens L36)  44* 252.15324−4.265268 45 −995.58003 −37.825368 1.559238 (lens L37) 46 262.29146−1.000000 47 −210.53420 −30.482411 1.559238 (lens L38) 48 −8044.39654−1.002741 49 −124.46496 −36.754604 1.559238 (lens L39) 50 −627.72968−9.489076 51 534.41093 −27.941522 1.559238 (lens L310) 52 −9748.42213−1.007391 53 −131.28658 −50.000000 1.559238 (lens L311) 54 ∞ −12.503787(wafer surface) (Aspherical data) Surface 2 r = 1161.26854 κ = 0.000000C₄ = 0.141234 × 10⁻⁷ C₆ = 0.566669 × 10⁻¹² C₈ = 0.141094 × 10⁻¹⁶ C₁₀ =−0.504032 × 10⁻²⁰ C₁₂ = 0.747533 × 10⁻²⁴ C₁₄ = −0.400565 × 10⁻²⁸ Surface11 r = −147.64267 κ = 0.000000 C₄ = 0.117741 × 10⁻⁶ C₆ = −0.764549 ×10⁻¹¹ C₈ = −0.441188 × 10⁻¹⁵ C₁₀ = 0.122309 × 10⁻¹⁸ C₁₂ = −0.114006 ×10⁻²² C₁₄ = 0.478194 × 10⁻²⁷ Surface 20 r = 644.69642 κ = 0.000000 C₄ =0.378434 × 10⁻⁷ C₆ = −0.751663 × 10⁻¹² C₈ = 0.247735 × 10⁻¹⁶ C₁₀ =−0.222239 × 10⁻²⁰ C₁₂ = 0.256558 × 10⁻²⁴ C₁₄ = −0.235204 × 10⁻²⁸ Surface24 and surface 28 (same surface) r = 165.28528 κ = 0.000000 C₄ =−0.236840 × 10⁻⁷ C₆ = 0.766085 × 10⁻¹² C₈ = −0.122244 × 10⁻¹⁶ C₁₀ =−0.209608 × 10⁻²¹ C₁₂ = 0.109632 × 10⁻²⁵ C₁₄ = −0.837618 × 10⁻³⁰ Surface32 r = −8761.14467 κ = 0.000000 C₄ = 0.138366 × 10⁻⁷ C₆ = −0.162646 ×10⁻¹² C₈ = 0.264075 × 10⁻¹⁷ C₁₀ = 0.265565 × 10⁻²² C₁₂ = −0.494187 ×10⁻²⁶ C₁₄ = −0.786507 × 10⁻³¹ Surface 44 r = 252.15324 κ = 0.000000 C₄ =0.697432 × 10⁻⁸ C₆ = −0.714444 × 10⁻¹² C₈ = 0.747474 × 10⁻¹⁷ C₁₀ =−0.699569 × 10⁻²¹ C₁₂ = 0.228691 × 10⁻²⁵ C₁₄ = −0.160543 × 10⁻²⁹(Corresponding values of conditions) β1 = −0.650 β2 = −0.885 β3 = −0.434L1 = 347.8 mm L2 = 311.9 mm E = 453.1 mm D = 473.4 mm (1) |β2| = 0.885(2) |L1 − L2| / |L1| = 0.103 (3) |β| / |β1| = 0.385 (4) |E − D| / |E| =0.045

[0112]FIG. 7 are charts showing the lateral aberrations in the secondembodiment.

[0113] In the aberration charts, Y represents the image height, solidlines the wavelength 157.624 μm, broken lines 157.624+1 pm =157.625 nmand dashed lines 157.624−1 pm=157.623 nm, respectively.

[0114] As is evident from the aberration charts, it is known that thechromatic aberrations are well corrected for the exposure light with awavelength of 157.624±1 pm in the second embodiment similar to in thefirst embodiment.

[0115] Embodiment 3

[0116] In the first and second embodiments, both the first optical pathfolding mirror 1 and the second optical path folding mirror 2 areconstituted as front surface reflecting mirrors. Moreover, in the firstand second embodiments, the angular widths of a beam incident into thereflecting plane of the first optical path of a folding mirror 1 and thereflecting plane of the second optical path of a folding mirror 2increase in proportion to the numerical of aperture on the image side ofthe catadioptric optical system. In this case, if the reflecting planesare formed of a dielectric multilayer film, the reflectivity changeswith the incident angle and the phase of a reflected wave disperses withthe incident angle, thus it is difficult to ensure good angularcharacteristics. Therefore, it is preferable that the reflecting planesare formed of a metal film to obtain good angular characteristics, suchas a reflectivity nearly constant for a wide range of incident angles.However, the reduction of reflectivity arises if the metal is subjectedto irradiation of the F₂ laser in an atmosphere containing littleoxygen.

[0117] Accordingly, both the first optical path folding mirror 1 and thesecond optical path folding mirror 2 are constituted as rear (back)surface reflecting mirrors in the third embodiment. More specifically,as shown in FIG. 13B, the first optical path folding mirror 1 is formedas a right-angle prism having a plane of incidence 1 a perpendicular tothe optical axis AX1 of a first imaging optical system G1, a reflectingplane 1 b inclined to the optical axis AX1 at an angle of 45° and aplane of emergence 1 c perpendicular to the optical axis AX2 of a secondimaging optical system G2. The second optical path folding mirror 2 isformed as a right-angle prism having a plane of incidence 2 aperpendicular to the optical axis AX2 of the second imaging opticalsystem G2, a reflecting plane 2 b inclined to the optical axis AX1 at anangle of 45° and a plane of emergence 2 c perpendicular to the opticalaxis AX3 of a third imaging optical system G3.

[0118] Moreover, the first optical path folding mirror 1 and the secondoptical path folding mirror 2 are integrally constituted as one opticalpath folding mirror FM. Then, the optical axis AX1 of the first imagingoptical system G1 and the optical axis AX3 of a third imaging opticalsystem G3 are so set up that they linearly extend and constitute asingle common optical axis, i.e., a reference optical axis AX.Furthermore, the intersection line of the rear (back) surface reflectingplane 1 b of first optical path folding mirror 1 and the rear (back)surface reflecting plane 2 b of second optical path folding mirror 2 areset up so that the optical axis AX1 of the first imaging optical systemG1, the optical axis AX2 of the second imaging optical system G2 and theoptical axis AX3 of the third imaging optical system G3 intersect at onepoint (reference point).

[0119] As described above, both the first optical path folding mirror 1and the second optical path folding mirror 2 are constituted as rear(back) surface reflecting mirrors in the third embodiment.

[0120] Therefore, the rear (back) surface reflecting plane 1 b of thefirst optical path folding mirror 1 and the rear (back) surfacereflecting plane 2 b of the second optical path folding mirror 2 are notsubjected to the irradiation of F₂ laser in an oxygen-containingatmosphere. As a result, the reduction of reflectivity caused by the F₂laser irradiation can be avoided, even if the reflecting planes areformed of a metal film to obtain good angular characteristics, such as areflectivity that is nearly constant for a wide range of incidentangles.

[0121] Moreover, if the reflecting planes (1 b, 2 b) and thetransmitting planes (1 a, 1 c, 2 a, 2 c) of the first optical pathfolding mirror 1 and the second optical path folding mirror 2 arelocated in the vicinity of the formation position of a firstintermediate image and a second intermediate image, flaws, defects ofcoating, dust and the like on these planes are transferred to the wafersurface. Furthermore, setting a reduced length from a reticle R to waferW results in the miniaturization of the apparatus. The compact nature ofthe apparatus is also favorable in transportation.

[0122] Accordingly, in the third embodiment, the first intermediateimage is formed between the emergent plane 1 c of the first optical pathfolding mirror 1 and a concave reflecting mirror CM. The secondintermediate image is formed between the concave reflecting mirror CMand incident plane 2 a of the second optical path folding mirror 2. Thethird embodiment is specifically described below.

[0123]FIG. 13A is a diagram illustrating the lens construction of acatadioptric optical system (projection optical system PL) according tothe third embodiment. As in the first and second embodiments, thepresent invention is also applicable to a projection optical system inwhich aberrations including chromatic aberrations are corrected for anexposure light with a wavelength of 157.624 mn ±1 pm in the thirdembodiment.

[0124] In the catadioptric optical system of FIG. 13A, the first imagingoptical system G1 comprises a positive meniscus lens L11 having anaspherical concave surface facing to the wafer side, a negative meniscuslens L12 having a concave surface facing to the reticle side, a biconvexlens L13, a positive meniscus lens L14 having a convex surface facing tothe reticle side, a positive meniscus lens L15 having a convex surfacefacing to the reticle side, a positive meniscus lens L16 having anaspherical concave surface facing to the reticle side, a positivemeniscus lens L17 having a concave surface facing to the reticle side, apositive meniscus lens L18 having a concave surface facing to thereticle side, a biconvex lens L19 and a positive meniscus lens L110having an aspherical concave surface to the wafer side in order from thereticle side.

[0125] The second imaging optical system G2 comprises a negativemeniscus lens L21 having a concave surface facing to the reticle side, anegative meniscus lens L22 having an aspherical concave surface facingto the reticle side and a concave reflecting mirror CM in order from thereticle side along the propagative route of light (i.e., the incidentside).

[0126] The third imaging optical system G3 comprises a biconvex lens L31having an aspherical convex surface facing the reticle side, a biconvexlens L32, a positive meniscus lens L33 having a convex surface facing tothe reticle side, a biconcave lens L34, a biconvex lens L35, an aperturestop AS, a negative meniscus lens L36 having an aspherical convexsurface facing to the wafer side, a biconvex lens L37, a biconvex lensL38, a positive meniscus lens L39 having a convex surface facing to thereticle side, a negative meniscus lens L310 having a concave surfacefacing to the reticle side and a plano-convex lens L311 having a planesurface to the wafer side in order from the reticle side along thepropagative route of light.

[0127] Values of data of the catadioptric optical system of the thirdembodiment are identified in the following table (3). In the table (3),λ represents the wavelength of exposure light, β the projectionmagnification (magnification of whole system), NA represents thenumerical aperture on the image side (wafer side), B represents theradius of image circle IF on the wafer W, A represents the off-axisquantity of an effective exposure region ER, LX the dimension of theeffective exposure region ER along the X direction (dimension of longside), and LY represents the dimension of the effective exposure regionER along the Y direction (dimension of the short side), respectively.

[0128] Moreover, surface no. represents the order of surfaces from thereticle side along the propagative direction of light from the reticlesurface which is an object surface (first surface) to the wafer surfacebeing the image surface (second surface), r the curvature radius ofsurface (vertex curvature radius in the case of the aspherical surface:mm), d the axial space of surface, i.e., surface distance (nun), and nthe dioptric index to the wavelength, respectively.

[0129] Furthermore, the surface distance d changes its sign withreflected degree. Therefore, the sign of the surface distance d is takenas negative on the optical path from the first optical path foldingmirror 1 to the concave reflecting mirror CM and on the optical pathfrom the second optical path folding mirror 2 to the image surface, andis taken as positive in other optical paths. Then, the curvature radiusof convex surface facing to the reticle side is taken as positive andthe curvature radius of the concave surface facing to the reticle sideis taken as negative in the first imaging optical system G1. On theother hand, the curvature radius of concave surface facing to thereticle side is taken as positive and the curvature radius of convexsurface facing to the reticle side is taken as negative in the thirdimaging optical system G3. The curvature radius of concave surfacedirecting to the reticle side (i.e., the incident side) is taken aspositive and the curvature radius of convex surface facing to thereticle side (i.e., the dent side) is taken as negative along thepropagative route of light in the second ging optical system G2. TABLE 3(Main data) λ = 157.624 nm β = −0.25 NA = 0.75 B = 14.6 mm A = 3 mm LX =22 mm LY = 6.6 mm (Data of optical members) Surface no. r d n (reticlesurface) 78.905334  1 342.16576 16.022696 1.559307 (lens L11)  2*991.85390 17.753350  3 −219.16547 12.000000 1.559307 (lens L12)  4−320.00000 1.000000  5 2955.64579 26.141043 1.559307 (lens L13)  6−246.44297 1.000000  7 194.21831 26.260817 1.559307 (lens L14)  81329.96976 1.000000  9 107.60955 40.108611 1.559307 (lens L15) 10113.33032 159.676621  11* −148.84038 49.913127 1.559307 (lens L16) 12−120.00000 1.000000 13 −222.95345 20.859126 1.559307 (lens L17) 14−150.00000 1.000000 15 −401.55577 23.223530 1.559307 (lens L18) 16−183.82866 1.000000 17 521.59548 25.488040 1.559307 (lens L19) 18−467.35041 1.000000 19 163.47702 24.187152 1.559307 (lens L110)  20*493.47675 59.076923 21 ∞ 42.000000 1.559307 (incident plane of firstoptical path folding mirror 1) 22 ∞ −5.000000 1.559307 (reflecting planeof first optical path folding mirror 1) 23 ∞ −288.258092 (emergent planeof first optical path folding mirror 1) 24 117.68987 −20.000000 1.559307(lens L21) 25 494.06295 −20.317103  26* 162.15533 −23.222125 1.559307(lens L22) 27 424.56556 −30.146320 (concave reflecting mirror) 28174.51441 30.146320 29 424.56556 23.222125 1.559307 (lens L22)  30*162.15533 20.317103 31 494.06295 20.000000 1.559307 (lens L21) 32117.68987 288.258092 33 ∞ 5.000000 1.559307 (incident plane of secondoptical path folding mirror 2) 34 ∞ −42.000000 1.559307 (reflectingplane of second optical path folding mirror 2) 35 ∞ −75.000000 (emergentplane of second optical path folding mirror 2)  36* −4472.59851−25.928698 1.559307 (lens L31) 37 261.48119 −1.000000 38 −702.65223−25.574812 1.559307 (lens L32) 39 484.70684 −1.000000 40 −171.00841−36.095030 1.559307 (lens L33) 41 −824.20256 −52.106994 42 11305.93183−29.474446 1.559307 (lens L34) 43 −116.92116 −179.952947 44 −250.00000−35.678589 1.559307 (lens L35) 45 613.05439 −28.469304 46 ∞ −24.889346(aperture stop AS) 47 165.48519 −20.183765 1.559307 (lens L36)  48*279.53959 −1.000000 49 −1112.01574 −39.557019 1.559307 (lens L37) 50293.63544 −1.000000 51 −227.08614 −39.175338 1.559307 (lens L38) 523890.58196 −8.150754 53 −120.00000 −39.612810 1.559307 (lens L39) 54−519.19928 −10.442215 55 457.48024 −21.591566 1.559307 (lens L310) 562169.78959 −1.000000 57 −132.52125 −50.000000 1.559307 (lens L311) 58 ∞−12.499991 (wafer surface) (Aspherical data) Surface 2 r = 991.85390 κ =0.000000 C₄ = 0.117208 × 10⁻⁷ C₆ = 0.310236 × 10⁻¹² C₈ = 0.401356 ×10⁻¹⁷ C₁₀ = −0.265435 × 10⁻²⁰ C₁₂ = 0.412618 × 10⁻²⁴ C₁₄ = −0.238346 ×10⁻²⁸ Surface 11 r = −148.84038 κ = 0.000000 C₄ = 0.637735 × 10⁻⁷ C₆ =−0.462907 × 10⁻¹¹ C₈ = −0.137097 × 10⁻¹⁵ C₁₀ = 0.475629 × 10⁻¹⁹ C₁₂ =−0.370236 × 10⁻²³ C₁₄ = 0.833198 × 10⁻²⁸ Surface 20 r = 493.47675 κ =0.000000 C₄ = 0.280809 × 10⁻⁷ C₆ = −0.360031 × 10⁻¹² C₈ = 0.929800 ×10⁻¹⁷ C₁₀ = −0.100162 × 10⁻²⁰ C₁₂ = 0.116050 × 10⁻²⁴ C₁₄ = −0.979417 ×10⁻²⁹ Surface 26 and Surface 30 (same surface) r = 162.15533 κ =0.000000 C₄ = −0.235140 × 10⁻⁷ C₆ = −0.709685 × 10⁻¹² C₈ = −0.957183 ×10⁻¹⁷ C₁₀ = −0.947024 × 10⁻²² C₁₂ = 0.274134 × 10⁻²⁶ C₁₄ = −0.469484 ×10⁻³⁰ Surface 36 r = −4472.59851 κ = 0.000000 C₄ = 0.108255 × 10⁻⁷ C₆ =−0.135832 × 10⁻¹² C₈ = 0.188102 × 10⁻¹⁷ C₁₀ = −0.163001 × 10⁻²² C₁₂ =0.128506 × 10⁻²⁶ C₁₄ = −0.312367 × 10⁻³⁰ Surface 48 r = 279.53959 κ =0.000000 C₄ = 0.176353 × 10⁻⁷ C₆ = −0.889127 × 10⁻¹² C₈ = 0.132824 ×10⁻¹⁶ C₁₀ = −0.701110 × 10⁻²¹ C₁₂ = 0.104172 × 10⁻²⁵ C₁₄ = −0.327893 ×10⁻³⁰ (Corresponding values of conditions) β1 = −0.650 β2 = −0.865 β3 =−0.445 L1 = 320.8 mm L2 = 365.2 mm E = 466.7 mm D = 455.6 mm (1) |β2| =0.865 (2) |L1 − L2| / |L1| = 0.138 (3) |β| / |β1| = 0.385 (4) |E − D| /|E| = 0.024

[0130]FIG. 14 are charts illustrating the lateral aberrations in thethird embodiment.

[0131] In the aberration charts, Y represents the image height, thesolid lines represent the wavelength 157.624 nm, the broken linesrepresent wavelength 157.624+1 pm=157.625 nm and the dashed linesrepresent wavelength 157.624−1 pm=157.623 nm, respectively.

[0132] As is evident from the aberration charts, it is known that thechromatic aberrations can be corrected for the exposure light with awavelength of 157.624±1 pm in the third embodiment as similarlycorrected in the first and second embodiments.

[0133] As described above, in the first to third embodiments, the imageside, having a NA of 0.75, can be provided and the image circle withradius of 14.6 mm, in which the aberrations beginning with the chromaticaberrations are corrected, can be provided on the wafer. Therefore, ahigh resolution of about 0.1 μm can be obtained in addition to providinga rectangular effective exposure region that is approximately 22 mm ×6.6mm.

[0134] Moreover, in the first to third embodiments, an off-axis quantityA as small as about 3 mm can be set up on the wafer W because the secondimaging optical system G2 has a nearly unit (equal) magnification β2 andthe optical path separation is provided in the vicinity of the twointermediate images formed by a mutual approach. As a result, arectangular effective exposure region approximately as large as 22 mm×6.6 mm can be provided in the image circle that is as small as about14.6 mm in radius. Thus, an optical system superior in aberrationcorrection, miniaturization, optical adjustment, mechanical design, andin cost of manufacturing can be obtained.

[0135] Furthermore, in the first to third embodiments, the reticle R andthe wafer W can be arranged in parallel to each other and along a planeperpendicular to the direction of gravity (i.e., horizontal plane). Allthe lenses constituting the first imaging optical system G1 and thethird imaging optical system G3 can be arranged in parallel along asingle optical axis AX of the direction of gravity because the firstimaging optical system G1 and the third imaging optical system G3 areprovided in an upright position along the common reference optical axisAX. Accordingly, the reticle R, the wafer W and most of lensesconstituting the projection optical system PL (91% in number for all theembodiments) are parallel, and are not subject to asymmetricaldeformation caused by their own weight. Likewise, optical adjustment,mechanical design and high resolution are advantageously ensured.

[0136] Additionally, in the first to third embodiments, the intersectionline of the reflecting planes of the first optical path folding mirror 1and the second optical path folding mirror 2 are set up so that theoptical axis AX1 of the first imaging optical system G1, the opticalaxis AX2 of the second imaging optical system G2 and the optical axisAX3 of the third imaging optical system G3 intersect at one point(reference point). The first optical path folding mirror 1 and thesecond optical path folding mirror 2 are integrally formed as atriagonal prism member in which the top side and the bottom side areshaped into right angled isosceles triangles, i.e., one optical pathfolding mirror FM. As a result, the stability of the optical systemincreases. The optical adjustment and mechanical design are simplebecause it is possible to position the three optical axes AX1-AX3 andthe ridge lines of the optical path folding mirror FM in connection atone reference point. In addition, the high-accuracy optical adjustmentis simple and the optical systems have higher stability because theoptical axis AX2 of the second imaging optical system G2 is set up sothat it is perpendicular to the reference optical axis AX which is thecommon optical axis of the first imaging optical system G1 and the thirdimaging optical system G3.

[0137] Furthermore, in the first, second and third embodiments, theintersection line of reflecting planes of the first optical path foldingmirror 1 and the second optical path folding mirror 2 are set up so thatthe optical axis AX1 of the first imaging optical system G1, the opticalaxis AX2 of the second imaging optical system G2 and the optical axisAX3 of the third imaging optical system G3 intersect at one point(reference point) as described above. As shown in the alternative, FIGS.15 and 16, illustrate an intersection line of reflecting planes of thefirst optical path folding mirror 1 and the second optical path foldingmirror 2 which is not located at the intersection of the optical axisAX1 of the first imaging optical system G1, the optical axis AX2 of thesecond imaging optical system G2 and the optical axis AX3 of the thirdimaging optical system G3.

[0138]FIG. 15 is a schematic block diagram of a catadioptric opticalsystem based on modification example 1. In the catadioptric opticalsystem shown in FIG. 15, the optical axis AX1 of the first imagingoptical system G1 and the optical axis AX3 of the third imaging opticalsystem G3 are coincident. The intersection line of reflecting planes ofthe first optical path folding mirror 1 and the second optical pathfolding mirror 2 is located on the side opposite to the concave mirrorCM for the optical axis AX1 of the first imaging optical system G1 andthe optical axis AX3 of the third imaging optical system G3.

[0139]FIG. 16 is a schematic block diagram of a catadioptric opticalsystem based on modification example 2. In the catadioptric opticalsystem shown in FIG. 16, the optical axis AX1 of the first imagingoptical system G1 and the optical axis AX3 of the third imaging opticalsystem G3 are coincident. The intersection line of reflecting planes ofthe first optical path folding mirror 1 and the second optical pathfolding mirror 2 is located on the side of concave mirror CM for theoptical axis AX1 of the first imaging optical system G1 and the opticalaxis AX3 of the third imaging optical system G3.

[0140] Moreover, in previous examples, the optical axis AX1 of the firstimaging optical system G1 and the optical axis AX2 of the second imagingoptical system G2 are orthogonal and the optical axis AX2 of the firstimaging optical system G2 and the optical axis AX3 of the third imagingoptical system G3 are orthogonal. However, they may also be constitutedso that the optical axis AX1 of the first imaging optical system G1, theoptical axis AX2 of the second imaging optical system G2 and the opticalaxis AX3 of the third imaging optical system G3 are non-orthogonal. See,e.g., modification example 3 shown in FIG. 17.

[0141] Furthermore, in previous examples, the optical axis AX1 of thefirst imaging optical system G1 and the optical axis AX3 of the thirdimaging optical system G3 are coincident. However, a construction inwhich the optical axis AX1 of the first imaging optical system G1 andthe optical axis AX3 of the third imaging optical system G3 shift inparallel to each other is also possible. See, e.g., modification example4 shown in FIG. 18. In the modification example 4 shown in FIG. 18, theintersection line of the first optical path folding mirror 1 and thesecond optical path folding mirror 2 is not coincident with the opticalaxis AX1 of the first imaging optical system G1 and the optical axis AX3of the third imaging optical system G3. The intersection line of thefirst optical path folding mirror 1 and the second optical path foldingmirror 2 may also be constituted so that it is coincident with theintersection of optical axis AX1 of the first imaging optical system G1and optical axis AX2 of the second imaging optical system G2 or theintersection of optical axis AX2 of the second imaging optical system G2and optical axis AX3 of the third imaging optical system G3.

[0142] Additionally, in previous examples, the optical axis AX1 of thefirst imaging optical system G1 and the optical axis AX3 of the thirdimaging optical system G3 are in parallel to (coincident with) eachother (the axis AX1 of the first imaging optical system G1 and the axisAX2 of the second imaging optical system G2 are made orthogonal and theaxis AX2 of the second imaging optical system G2 and the axis AX3 of thethird imaging optical system G3 are made orthogonal). However, aconstruction in which the optical axis AX1 of the first imaging opticalsystem G1 and the optical axis AX3 of the third imaging optical systemG3 are not parallel to each other is also possible. See, e.g.,modification example 5 shown in FIG. 19. In the modification example 5shown in FIG. 19, the intersection line of reflecting planes of thefirst optical path folding mirror 1 and the second optical path foldingmirror 2 is set up so that it intersects with the optical axis AX1 ofthe first imaging optical system G1, the optical axis AX2 of the secondimaging optical system G2 and the optical axis AX3 of the third imagingoptical system G3 at one point (reference point). However, they may alsobe constituted so as not to intersect at the reference point. See, e.g.,the modification example 2 shown in FIG. 15 and FIG. 16.

[0143] Next, a detailed construction of the projection exposureapparatus of the embodiment shown in FIG. 2 is described below.

[0144]FIG. 8 is a diagram showing the general construction of theprojection exposure apparatus of the embodiment shown in FIG. 2. FIG. 9is an enlarged diagram which shows a portion of to the illuminationoptical system of the projection exposure apparatus of FIG. 8. FIG. 10is an enlarged diagram which shows a portion of the projection opticalsystem of the projection exposure apparatus of FIG. 8.

[0145] First, a detailed construction of the portion of the illuminationoptical system IL of FIGS. 8-9 is described.

[0146] The projection exposure apparatus is provided with a F₂ laserlight source 100, e.g., 156.624 nm in wavelength used in a naturaloscillation (almost half width 1.5 pm). However, the application of anArF excimer laser light source of about 193 rnm, a KrF excimer lightsource of about 248 mn, an Ar₂ laser light source and the like can alsobe used in the present invention. The light source 100 may be arrangedon the lower floor where the main body of the exposure apparatus. Anexclusive area (footprint) of main body of the exposure apparatus can bedecreased and an influence of vibrations on the main body of theexposure apparatus can also be reduced.

[0147] A light from the light source 100 is led into the inside of afirst illumination system casing 110 via a beam matching unit (BMU) 101.The first illumination system casing 110 receives movable opticalelements inside it and supports them by a supporting member 210 on abase plate 200. The beam matching unit 101 contains a movable mirrormatching an optical path between the light source 100 and an the mainbody of the exposure apparatus. Moreover, the optical path between thelight source 100 and the beam matching unit 101 is optically connectedby a cylinder (tube) 102, and an optical path between the beam matchingunit 101 and the first illumination system casing 110 is opticallyconnected by a cylinder (tube) 103. Nitrogen or a rare gas (inert gas),such as helium and the like, is filled in the optical path of thecylinder 102 and cylinder 103.

[0148] The light led into the inside of the first illumination systemcasing 110 passes through a micro fly's eye lens 111 (an optical systemequivalent to a first fly's eye lens), and lens groups 112, 113constituting an afocal zoom relay optical system (a both sidetelecentric zoom optical system), and then comes to a turret 114 forloading plural diffraction array optical elements or dioptric arrayoptical elements. The micro fly's eye lens 111 is an optical systemcomprising many fine (micro) lenses having a positive dioptric power andarranged vertically and horizontally in a dense arrangement. Generally,the micro fly's eye lens 111 is constituted, e.g., by applying anetching treatment to a parallel plane glass plate to form the fine lensgroups. Diffraction array optical elements disclosed in U.S. Pat. No.5,850,300 can be used as the diffraction array optical elements, anddioptric array optical elements disclosed in WO 99/49505 (EP 1,069,600),wherein the elements are formed on one substrate by an etching techniquecan be used as the dioptric array optical elements.

[0149] U.S. Pat. No. 5,850,300 and WO 99/49505 (EP 1,069,600) areincorporated herein by reference.

[0150] In the plural diffraction array optical elements or the dioptricarray optical elements supported by the turret 114, a light passingthrough one diffraction, or dioptric, array optical element positionedin the illuminating optical path incides into a micro fly's eye lens 117via a focal zoom optical system (115, 116). A front focal point of theafocal zoom optical system (115, 116) is positioned in the vicinity ofthe diffraction array optical element or the dioptric array opticalelement of the turret 114. The micro fly's eye lens 117 is an opticalsystem equivalent to a second fly's eye lens. The micro fly's eye lens117 includes many fine lenses which are much finer than fly's eye lensesand produces a large wave front dividing effect. Thus, an illuminatingaperture stop is not provided on its emergent side (back focus plane).The micro fly's eye lens 117 is constituted by a pair of micro fly's eyelenses at a space along the optical axis, and an aspherical surface mayalso be introduced into its refracting surface. This constructionresults in the suppression of the occurrence of a coma aberration in themicro fly's eye lens 117 and suppresses the occurrence of unevenilluminance distribution on the reticle. Furthermore, a turret type stopprovided with a iris stop, a annular aperture and a quadrupole aperturemay also be arranged in the vicinity of rear focal plane of the microfly's eye lens 117.

[0151] The light exiting from the micro fly's eye lens 117 illuminates amovable blind mechanism 120 superimposed via a condenser optical system(118, 119). The front focal position of the movable blind mechanism 120is positioned in the vicinity of position of a surface light source(plural light source images) formed by the micro fly's eye lens 117. Themovable blind mechanism 120 is provided with a fixed illumination fieldstop (fixed blind) 121 with a slit aperture and a movable blind 122 forvarying the width of an illumination field region in the scanningdirection. The movable blind 122 allows for a decrease in the movingstroke of a reticle stage in the scanning direction and a decrease inthe width of shading zone (frame) of reticle. Moreover, the fixed blind121 is arranged together with the reticle. The construction of themovable blind mechanism 120 is disclosed in Japan Kokai 4-196513 (U.S.Pat. No. 5,473,410).

[0152] U.S. Pat. No. 5,473,410 is incorporated herein by reference.

[0153] The light passing through the movable blind mechanism 120 emitsfrom the first illumination system casing 110 and is led to the insideof a second illumination system casing 130. An imaging optical system ofthe illuminating field stop is provided for reimaging the illuminatingfield stop on the reticle by a given enlargement magnification. The lensgroups (131-134) and optical path folding mirrors (135, 136), whichconstitute the illumination field stop imaging optical system must notbe used for a vibration source because they are fixed to the secondillumination system casing 130. The second illumination system casing130 is supported by a supporting member 211 on the base plate 200. Themagnification factor of the imaging optical system of illuminating fieldstop may be equal to (unity) or a reduced ratio.

[0154] Driving units (142, 143) for driving the lens groups (112, 113)of the afocal zoom relay optical system in the direction of optical axisare arranged in the first illumination system casing 110. The drivingunits (142, 143) are mounted to the outer side of the first illuminationsystem casing 110 to prevent the contamination in the illuminatingoptical path. A driving unit 144 for rotationally driving the turret 114and driving units 145, 146 for driving the lens groups (115, 116)constituting the afocal zoom relay optical system in the direction ofoptical axis are mounted to the outer side of the first illuminationsystem casing 110 to prevent the contamination in the illuminatingoptical path.

[0155] Driving units (147, 148) for driving the lens groups (118, 119)constituting the condenser optical system in the direction of opticalaxis, rotating at least one lens group with an axis perpendicular to theoptical axis as center and moving (offsetting) the other lens group inthe direction perpendicular to the optical axis are mounted to the outerside of the first illumination system casing 110. The focal length ofthe condenser optical system can be changed and in its turn the size ofan illumination region formed on a wafer and the illumination NA(numerical aperture) can be properly changed on the reticleindependently of each other by movement of the lens groups (118, 119) inthe direction of optical axis. Controls of slanted illuminance (inclinedilluminance distribution) on the wafer surface and slanted (inclined)telecentricity are obtained by the rotation and offset of the lensgroups (118, 119). An illuminance control symmetrical to the opticalaxis on the wafer surface is obtained by moving one lens group in thedirection of the optical axis separately from a previous illuminationfield variable.

[0156] Furthermore, a tube 151 for allowing nitrogen or a rare gas(inert gas), such as helium and the like, to flow into the inside of thefirst illumination system casing 110, and a tube 152 for allowingnitrogen or a rare gas (inert gas), such as helium and the like, todischarge from the first illumination system casing 110 are arranged onthe outer side thereof. Valves (161, 162) for controlling the gas inflowrate/outflow rate are arranged at the tubes (151, 152), respectively. Ifthe inert gas is helium, the tubes (151, 152) are connected to a heliumrecovery/regeneration unit, e.g., disclosed in Japan Kokai 11-219902 (WO99/25010, EP 1,030,351).

[0157] EP 1,030,351 is incorporated herein by reference.

[0158] A tube 153 for allowing nitrogen or a rare gas (inert gas), suchas helium and the like, to flow into the inside of the secondillumination system casing 130 and a tube 154 for allowing nitrogen or arare gas (inert gas), such as helium and the like, to discharge from thesecond illumination system casing 130 are arranged on the outer sidethereof. Valves (163, 164) for controlling the gas inflow rate/outflowrate are arranged at the tubes (153, 154), respectively. If the inertgas is helium, the tubes (153, 154) are also connected to the previouslymentioned helium recovery/regeneration unit.

[0159] A bellows 170 is provided for connecting the first illuminationsystem casing 110 and the movable blind mechanism 120. Another bellows171 is provided for connecting the movable blind mechanism 120 and thesecond illumination system casing 130. The bellows 170, 171 are formedof a material which has a certain degree of flexibility and rigiditythat is not so great as to deform and to ensure less degassing, e.g., ametal or a material given by coating a rubber or resin with aluminum andthe like.

[0160] In the illumination optical system IL arranged as above, a beamincident from the laser light source 100 to the micro fly's eye lens 111is divided two-dimensionally by many fine lenses, and one light sourceimage is formed on the back focal plane of each fme lens, respectively.The beam from the many light source images (surface light sources)formed at the back focal plane of the micro fly's eye lens 111 incidesinto one diffraction array optical element, e.g., a diffraction opticalelement for annular modified illumination, arranged in the illuminationoptical path by the turret 114 via the afocal zoom relay optical system(112, 113). The beam converted to rings via the diffraction opticalelement for annular modified illumination forms a annular illuminationfield at its back focal plane and in its turn at the incident plane ofthe micro fly's eye lens 117 via the afocal zoom optical system (115,116).

[0161] The beam inciding into the micro fly's eye lens 117 is dividedtwo-dimensionally by many fine lenses, and a light source image isformed on the back focal plane of each fine lens where the beam incides,respectively. Thus, many annular light sources (secondary surface lightsources) are provided (same as the illumination field formed by the beaminciding into the micro fly's eye lens 117). The light from thesesecondary surface light sources is subjected to a condensing action ofthe condenser optical system (118, 119) and then illuminates a givenplane optically together with the reticle R superimposed. Thus, arectangular illumination field similar to the shape of each fine lensconstituting the micro fly's eye lens 117 is formed on the fixed blind121 arranged at this given plane. The beam passing through the fixedblind 121 and the movable blind 122 of the movable blind mechanism 120is subjected to a condensing action of the imaging optical system ofillumination field stop (131-134) and then illuminates the reticle Rwith a given formed pattern evenly and superimposed.

[0162] Here, modified illuminations like annular modified illuminationor multipole (e.g., dipole (two-eyed), quadrupole (four-eyed), octapole(eight-eyed) and so on) modified illumination and conventional circularillumination can be imposed by switching the diffraction array opticalelements or the dioptric array optical elements arranged in theillumination optical path by the turret 114. In the case of the annularmodified illumination, for example, both the size (outer diameter) andshape (annular ratio) of a annular secondary light source can be changedby changing the magnification of the afocal zoom relay optical system(112, 113). Moreover, the outer diameter of the annular secondary lightsource can be changed by changing the focal length of the focal zoomoptical system (115, 116) without changing its annular ratio. Only theannular ratio of the annular secondary light source can be changed byproperly changing the focal length of the focal zoom optical system(115, 116) without changing the outer diameter of the light source.

[0163] A detailed construction of a portion of the projection opticalsystem PL is described hereafter, with reference to FIG. 8 and FIG. 10.

[0164] The described projection exposure apparatus is horizontallyarranged on the floor of a clean room and is provided with the baseplate (frame caster) 200 which becomes the datum of the apparatus.Plural supporting members (221, 222) are vertically arranged on the baseplate 200. Only two supporting members are shown in FIGS. 8 and 10, butfour supporting members are vertically arranged in practice. Threesupporting members may also be used.

[0165] Anti-vibration units (231, 232) for isolating vibrations from thefloor at a micro G level are mounted to the supporting members (221,222), respectively. In the anti-vibration units (231, 232), an air mountwith controllable internal pressure and an electromagnetic actuator(e.g., voice coil motor) are arranged in parallel or in series. Thetransmission of vibrations from the floor to a column 240 for holdingthe projection optical system is reduced by the action of theanti-vibration units (231, 232). A plurality of supporting members (251,252) for supporting a reticle stage fixed plate 301 are verticallyarranged on the column 240. In FIGS. 8 and 10, only two supportingmembers (251, 252) are shown, but they are actually four members (mayalso be three members).

[0166] The described projection exposure apparatus is provided with areticle stage RS float supporting on the reticle base fixed plate 301.The reticle stage RS is constituted so that the reticle R can belinearly driven in the Y-axis direction with a large stroke, and alsocan be driven in the X-axis, Y-axis directions and OZ (direction ofrotation around the Z axis) with a little driven amount.

[0167] Moreover, a reticle stage RS in which a reticle stage and areticle base between the reticle base fixed plate and the reticle stageis provided. The reticle base may be shifted so as to keep a momentum ina direction reverse to the direction of movement of the reticle stage.Such a reticle stage is disclosed, e.g., in Japan Kokai 11-251217 (U.S.patent application 260,544 filed on Mar. 2, 1999). Moreover, a reticlestage holding two reticles along the Y-axis direction (scanningdirection) as shown in Japan Kokai 10-209039 (EP 855,623) and JapanKokai 10-214783 (EP 951,054) may also be used as the reticle stage RS.

[0168] U.S. patent application 260,544, EP 855,623 and EP 951,054 areincorporated herein by reference.

[0169] A reticle interferometer RIF is arranged on the reticle basefixed plate 301 for measuring the position and the amount of movement ofthe reticle stage RS in the XY direction. One end of the reticle stageRS is a reflecting plane, which is a moving (measuring) mirror of thereticle interferometer RIF. A reticle chamber partition 310 for forminga space where an optical path in the vicinity of the reticle R is sealedwith an inert gas (nitrogen, helium and the like) is arranged on thereticle base fixed plate 301. A door for moving the reticle in or out ofa reticle stocker (not shown) may be provided. A reticle pool room fortemporarily receiving the reticle before moving the reticle into thereticle chamber and replacing the internal gas with an inert gas isarranged by adjoining it to the reticle chamber.

[0170] A bellows 321 for connecting the reticle chamber partition 310and the second illumination system casing 130 is arranged. The materialof the bellows 321 is similar to the previously mentioned bellows (170,171). A tube 331 for allowing nitrogen or a rare gas (inert gas), suchas helium and the like, to flow into the reticle chamber and a tube 332for allowing nitrogen or a rare gas (inert gas), such as helium and thelike, to discharge from the reticle chamber are arranged on the outerside of the reticle chamber partition 310. If the inert gas is helium,and the tubes (331, 332) may also be connected to the previouslymentioned helium recovery/regeneration unit.

[0171] Valves (341, 342) for controlling the gas inflow rate/outflowrate are arranged at the tubes (331, 332), respectively. Moreover, abellows 351 for connecting the reticle base fixed plate 301 and theprojection optical system is arranged. The material of the bellows 351is similar to the previously mentioned bellows 321. Thus, the space inthe vicinity of the reticle R is sealed by the action of the reticlechamber partition and the bellows (321, 351).

[0172] The projection exposure apparatus is provided with a wafer stagefixed plate 401. The wafer stage fixed plate 401 is horizontallysupported on the base plate 200 by the action of anti-vibration units(411, 412) for isolating vibrations from the floor at a micro G level.In the anti-vibration units (411, 412), an air mount with controllableinternal pressure and an electromagnetic actuator (e.g., voice coilmotor) may be arranged in parallel or in series. The wafer stage WS ismovable in the XY direction and is floatably loaded on the wafer stagefixed plate 401.

[0173] The wafer stage WS comprises a Z-eveling stage for inclination inthe biaxial direction of θ_(x) (direction of rotation around the X axis)and θ_(y) (direction of rotation around the Y axis) and movable in theZ-axis direction and a θ stage for making it movable in the θ_(Z)(direction of rotation around the Z axis) direction. For example, awafer stage disclosed in Japan Kokai 8-63231 (GB 2,290,658) can be usedas the wafer stage WS. Moreover, two wafer stages may also be arrangedas described in Japan Kokai 10-163097, Japan Kokai 10-163098, JapanKokai 10-163099, Japan Kokai 10-163100, Japan Kokai 10-214783 (EP951,054), or Japan Kokai 10-209039 (EP 855,623), WO 98/28665 or WO98/40791.

[0174] GB 2,290,658, EP 855,623, EP 951,054, WO 98/28665 and WO 98/40791are incorporated herein by reference.

[0175] A wafer table (wafer holder) WT for loading the wafer by vacuumsuction and/or electrostatic suction is arranged on the wafer stage WS.A wafer chamber partition 411 for forming a space where an optical pathin the vicinity of the wafer W is sealed with an inert gas (nitrogen,helium and the like) is arranged on a wafer stage fixed plate 401. Adoor for moving the wafer in or out of a reticle stocker (not shown) maybe provided. A reticle spare room for temporarily receiving wafersbefore moving the wafers into the wafer chamber and replacing theinternal gas with an inert gas is arranged by adjoining it to the waferchamber.

[0176] A sensor column SC is fixed to a lens barrel (or the column 240)of the projection optical system. An alignment sensor 421 for opticallymeasuring the position of an alignment mark on the wafer W in the XYtwo-dimensional direction is provided, an auto-focus leveling sensor 422for detecting the position of the wafer in the Z-axis direction (opticalaxis direction) and the inclinations of θ_(x), θ_(y) and θ_(Z) intriaxial direction and a wafer interferometer WIF for measuring theposition and amount of movement of the wafer table WT in the XYdirection are mounted to the sensor column SC.

[0177] At least one of a FIA (Field Image Alignment) system which themark position by illuminating an alignment mark on the wafer with alight having a broad wavelength region, such as a halogen lamp and thelike, and then processing this mark image, a LSA (Laser Step Alignment)system which measures the mark position by irradiating a laser light ona mark and then using a light diffracted and scattered by the mark and aLIA system (Laser Interferometric Alignment) which detects thepositional information of mark from its phase by irradiating a laserlight with only a little different frequency on an alignment mark likediffraction gratings from two directions and then interfering twodiffraction lights generated by the mark with each other is suitable forthe alignment sensor 421.

[0178] The auto-focus leveling sensor 422 detects whether the surface ofwafer to be exposed coincides (focuses) with the image surface of theprojection optical system. An auto-focus leveling sensor which detectsZ-axis direction positions of detection points in plural locationsarranged into a matrix is suitable for the auto-focus leveling sensor422. In this case, the detection points in plural locations are arrangedin a range including the slit-like exposure region formed by theprojection optical system.

[0179] The wafer interferometer WIF measures the position and the amountof movement of the wafer stage in the XY direction. One end of the waferstage WS becomes a reflecting plane. The reflecting plane becomes amoving (measuring) mirror of the wafer interferometer WIF. A tube 431for allowing nitrogen or a rare gas (inert gas), such as helium and thelike, to flow into the wafer chamber and a tube 432 for allowingnitrogen or a rare gas (inert gas), such as helium and the like, todischarge from the wafer chamber are arranged on the outer side of thewafer chamber partition 411.

[0180] If the inert gas is helium, the tubes (431, 432) can be connectedto the previously mentioned helium recovery/regeneration unit. Valves(441, 442) for controlling the gas inflow rate/outflow rate are arrangedat the tubes (431, 432), respectively. Moreover, a bellows 451 forconnecting the wafer chamber partition 411 and the sensor column SC isvertically arranged on the wafer stage fixed plate 401. The material ofthe bellows 451 is same, e.g., as the previously mentioned bellows 321.Thus, the space in the vicinity of the wafer W is sealed by the actionof the wafer chamber partition 411 and the bellows 451.

[0181] The described projection exposure apparatus is provided with aparallel plane plate L1 for covering a purge space in the projectionoptical system. The projection optical system is provided with a firstimaging optical system for forming a primary image (a first intermediateimage) of the pattern of the reticle R. The first imaging optical systemis composed of lenses (L2-L7: corresponding to L11-L110 in the firstimaging optical system of FIG. 2). The parallel plane plate L1 and thelenses (L2-L7) are received in divided barrels (501-507), respectively.Connection techniques between the divided barrels are disclosed in,Japan Kokai 7-86152 (U.S. Pat. No. 5,638,223). U.S. Pat. No. 5,638,223is incorporated herein as reference.

[0182] The parallel plane plate L1 is held by a cell 511. The cell 511holds the parallel plane plate L1 so as to be put between the topsurface and the under surface of the parallel plane plate L1. The heldlocations are plural locations (3 locations or more) in thecircumferential direction (θ_(z) direction) of the parallel plane plateLi. An air (gas)-tight structure is disposed between the parallel planeplate L1 and the cell 511. The lenses (L2-L7) are held by cells(512-517). The cells (512-517) hold the lenses (L2-L7) so as to be putbetween the top surface and the bottom surface of rims arranged at theperiphery of the lenses (L2-L7). The held locations are plural locations(3 locations or more) in the circumferential direction of the lenses.

[0183] The divided barrels (501-507) and the cells (511-517) areconnected by frames 521-527. Apertures for allowing an inert gas(helium) to pass inside of the projection optical system are arranged inthe frames 521-527 at plural locations along its circumferential(tangential) direction. An air (gas)-tight structure is disposed betweenthe frame 521 and the divided barrel 501.

[0184] In the first imaging optical system, an actuator 532 for movingthe lens L2 in the optical axis direction (Z direction) and inclining itin the θ_(x), θ_(y) directions is arranged. This actuator 532 isarranged at a pitch of 1200 in three locations which is equal distantfrom the optical axis and spaced in the circumferential direction (θ_(Z)direction). A linear motor, piezoelectric element, cylinder mechanismdriven by a pressure fluid or gas and the like can be used as theactuator 532. If the driven amount of actuator 532 is the same, the lensL2 can be moved in the optical axis direction. The lens L2 can beinclined in the θ_(X), θ_(y) direction by setting it up so that thedriven amount of the actuator 532 in three different locations isdifferent, respectively. Actuators 533, 535, 536, 537 operate similar toactuator 532.

[0185] In the first imaging optical system, an actuator 543 for movingthe lens L3 in the XY plane is arranged. These actuator 543 is betweenthe actuator 533 and a frame 523 and is arranged at a pitch of 120° inthree locations which are equal distant from the optical axis anddifferent in the circumferential direction (θ_(z) direction). A linearmotor, piezoelectric element, cylinder mechanism driven by a pressurefluid or gas and the like can be used as the actuator 543. A tube 551for allowing helium to flow into the inside of the projection opticalsystem is arranged in the divided barrel 511. This tube 551 may also beconnected to the previously mentioned helium recovery/regeneration unit.A valve 561 for controlling the gas inflow rate is arranged at the tube551.

[0186] The projection optical system is provided with an optical pathfolding mirror FM integrally formed by a first optical path foldingmirror and a second optical path folding mirror. The optical pathfolding mirror FM can be formed, e.g., by vapor deposition of a metal,such as aluminum and the like, on two side faces in a triagonal prismmember in which the top surface and the lower surface are in the shapeof right angled isosceles triangles. A dielectric multilayer film mayalso be vapor deposited in place of a metal film. As the materials ofdielectric multilayer film, metal fluorides such as aluminum fluoride,cryolite, chiolite, lithium fluoride, sodium fluoride, barium fluoride,calcium fluoride, magnesium fluoride, yttrium fluoride, ytterbiumfluoride, neodymium fluoride, gadolinium fluoride, lanthanum fluoride,osmium fluoride, strontium fluoride and the like can be used. Aconstruction in which a dielectric multilayer film is arranged on ametal film, such as aluminum and the like, may also be used. Thedielectric multilayer film functions as a protection coat for preventingthe metal film from oxidation. This dielectric multilayer film functionsto correct the phase difference between P polarization and Spolarization caused by a reflecting light from the metal film so as todecrease it and to correct a difference in phase difference between Ppolarization and S polarization due to the incident angle (emergentangle) (angular characteristic of PS phase difference) so as tohomogenize it in a desirable range of incident angles. If a phasedifference between P polarization and S polarization exists, this isundesirable because the imaging positions of an image due to the Ppolarization and an image due to the S polarization deviate and causethe deterioration of image quality on the imaging surface; thus adesirable resolution is not obtained. Moreover, two plane mirrors may bekept so as to perpendicularly intersect to each other in place offorming the first and the second optical path folding mirrors on onemember. In this case, it is considered that the two plane mirrors arekept adjustably, e.g., by a technique disclosed in Japan Kokai2000-28898, which is incorporated herein by reference.

[0187] The projection optical system is also provided with a secondimaging optical system for forming a second intermediate image (asecondary image of the pattern) nearly equal to the first intermediateimage in size, based on a light from the first intermediate image formedby the first imaging optical system. The second imaging optical systemis provided with lenses (L8, L9: corresponding to negative lenses L21, L22 in the second imaging optical system G2 of FIG. 2) and a concavereflecting mirror CM. SiC or a composite of SiC and Si can be used asthe material of the concave reflecting mirror CM. It is preferable tocoat the entire concave reflecting mirror CM with SiC fordegassification prevention. The reflecting surface of the concavereflecting mirror CM is formed by vapor deposition of metals, such as,e.g., aluminum and the like. A dielectric multi-layer film may also bevapor deposited in place of a metal film. In this case, as the materialsof dielectric multilayer film, metal fluorides such as aluminumfluoride, cryolite, chiolite, lithium fluoride, sodium fluoride, bariumfluoride, calcium fluoride, magnesium fluoride, yttrium fluoride,ytterbium fluoride, neodymium fluoride, gadolinium fluoride, lanthanumfluoride, osmium fluoride, strontium fluoride and the like can be used.A construction in which a dielectric multilayer film is arranged on ametal film, such as aluminum and the like, may also be used. Thedielectric multilayer film functions as a protection coat for preventingthe metal film from oxidation. This dielectric multilayer film enablesthe metal film to have a correcting function so as to decrease the phasedifference between P polarization and S polarization caused by areflecting light from the metal film. The correcting function nearlyhomogenizes a difference in phase difference between P polarization andS polarization caused by the incident angle (reflection angle) (angularcharacteristic of PS phase difference) in a desirable range of incidentangle. If the phase difference between P polarization and S polarizationexists, this is undesirable because the imaging positions of an imagedue to the P polarization and an image due to the S polarization deviateand cause the deterioration of image quality on the imaging surface anda desirable resolution is not obtained. The materials of the concavereflecting mirror can include ULE or Be. If Be is used, it is preferablethat the whole concave reflecting mirror CM is coated with SiC and thelike.

[0188] The optical folding mirror FM and the lens L8 are contained by adivided barrel 601, the lens L9 is contained by a divided barrel 602 andthe concave reflecting mirror CM is contained in a divided barrel 603. Aholding member 610 for holding the optical folding mirror FM is mountedto the divided barrel 601. A mechanism for adjusting the position of theoptical folding mirror FM (first and second optical folding mirrors) inthe θ_(x), θ_(y), θ_(Z) directions and its position in the XYZdirections may be arranged between this holding member 610 and thedivided barrel 601.

[0189] The lenses (L8, L9) of the second imaging optical system aresupported by supporting members (611, 612). Supporting members disclosedin Japan Kokai 6-250074 and Japan Kokai 11-231192 are suitable for thesesupporting members (611, 612). The concave reflecting mirror CM of thesecond imaging optical system is supported by a supporting member 613.Supporting members disclosed in Japan Kokai 6-250074, Japan Kokai11-231192 are suitable for this supporting member 613 and areincorporated herein by reference.

[0190] The projection optical system is further provided with a thirdimaging optical system for forming a final image (a reduced image of thepattern) on the wafer based on a light from the second intermediateimage formed by the second imaging optical system. The third imagingoptical system is provided with lenses (L10-L13: corresponding to thelenses L31-L311 in the third imaging optical system G3 of FIG. 2) and avariable aperture stop unit AS. The lens L110 is contained by a dividedbarrel 701 and the lens L11 is contained by a divided barrel 702. Aflange FL supported by a column 240 is arranged in the divided barrel702. Techniques for connection of the flange FL and the column 240, forexample, are disclosed in Japan Kokai 6-300955 (U.S. Pat. No. 5,576,895)and Japan Kokai 11-84199 are applicable. A sensor column SC is mountedto the flange FL. U.S. Pat. No. 5,576,895 is incorporated herein byreference.

[0191] The variable aperture stop AS is contained by a divided barrel703 and the lenses (L12, L13) are contained by divided barrels (704,705). The L10-L13 are supported by cells (711-712, 714-715),respectively. The structure of the cells (711-712, 714-715) is similarto that of the cell 512. An air (gas)-tight structure is disposedbetween the lens L13 and the cell 715 in the cell 715.

[0192] In the third imaging optical system, frames (721-722, 724-725)for connecting the divided barrels (701-702, 704-705) and the cells(711-712, 714-715) are arranged. Apertures for allowing an inert gas(helium) to flow into the inside of the projection optical system arearranged in plural locations along their circumferential direction inthe frames (721-722, 724-725). An air (gas)-tight structure is disposedbetween the cell 715 and the divided barrel 705.

[0193] In the third imaging optical system, actuators (731-732, 734) formoving the lens (L10-L12) in the optical axis direction and incliningthe imaging optical system in the θ_(x), θ_(y) directions are arranged.These actuators (731-732, 734) have construction similar to the actuator532. A tube 751 for allowing helium to discharge from the projectionoptical system is arranged in the divided barrel 705. This tube 751 isalso connected to the previously mentioned helium recovery/regenerationunit. A valve 761 for controlling the gas inflow rate is arranged at thetube 751.

[0194] Next, the embodiments of a manufacturing process wherein thepreviously mentioned exposure apparatus and an exposure method are usedin the lithographic process are described below.

[0195]FIG. 11 is a diagram showing the flowchart of a manufacturingprocess (semiconductor chips such as IC or LSI and the like, liquidcrystal panel, CCD, thin-film magnetic head, micro-machine and so on).As shown in FIG. 11, design step 201 illustrates a function/propertydesign (e.g., circuit design of semiconductor devices and the like) ofdevices (micro-devices) and a pattern design for obtaining the finctionsare also made (design step). Successively, a mask (reticle) for forminga designed circuit pattern is prepared in a step 202 (mask preparationstep). Alternatively, wafers can be manufactured with a material such assilicon and the like in a step 203 (wafer manufacture step).

[0196] Next, in the step 204 (wafer processing step), actual circuitsand the like are formed on the wafers by using wafers prepared in step201 and step 203 according to a lithographic technique and the like asdescribed later. Subsequently, in the step 205, the device assembly isconducted by using wafers processed in step 204. Such processes include,e.g., a dicing process, a bonding process and a packaging process (chipenclosure) and so on in step 205 according to demand.

[0197] Finally, in a step 206 (inspection step), inspections conductedinclude, e.g., an action confirmation test, a durability test and so onfor the devices prepared in step 205. After processing, the devices arecompleted and shipped.

[0198]FIG. 12 is a diagram showing one example of the wafer processingof step 204 in FIG. 11 for semiconductor devices. In FIG. 12, the wafersurface is oxidized in a step 211 (oxidation step). An insulating filmis formed on the wafer surface in a step 212 (CVD step). Electrodes areformed on the wafers by vapor deposition in a step 213 (electrodeformation step). An ion is implanted into the wafers in a step 214 (ionimplantation step). Steps 211 through step 214 constitute a pretreatmentprocess of the wafer processing, and are selected and executed accordingto the demand called for by the processing steps.

[0199] In the wafer processing steps, if the above pretreatment processhas been completed, a post-treatment process as follows is executed. Inthe post-treatment process, first, a sensitizer is applied to wafers ina step 215 (resist formation step). Successively, a circuit pattern ofmask given by the lithographic system (exposure apparatus) and exposuremethod described above is transferred on wafers in a step 216 (exposurestep). Next, the exposed wafers are developed in step 217 (developmentstep), and exposed members in a part, except for an area where theresist remains, are removed by etching in step 218 (etching step).After, the etching is finished, any unnecessary resist is removed instep 219 (resist removal step).

[0200] Circuit patterns are formed on the wafers by repeating the abovementioned pretreatment and post-treatment process steps.

[0201] If the manufacturing method of this embodiment is applied,devices with a high integrated level of about 0.1 μm in minimum linewidth can be produced with sufficient yield. The method applies the useof the exposure apparatus and the exposure method described above in theexposure process (step 216), thereby improving the resolving power of anexposure light in the vacuum ultraviolet region and producing highaccuracy exposure control.

[0202] Moreover, in this embodiment form, the tubes connected to theinside of the projection optical system are disposed in two locations.The number of tubes is not limited to only two locations. For example, anumber of tubes (inflow port/outflow outlet) corresponding to respectivelens chambers (spaces between optical members) may be arranged. Thepressure fluctuation of the gas in the projection optical system and theillumination optical system can be suppressed to a predetermined value.At this time, an allowable value of the pressure fluctuation is set upsuch that the value of the projection optical system more tight thanthat of the illumination optical system.

[0203] Furthermore, the pressure change of an inert gas filled orcirculated among optical elements of the illumination system andprojection optical system is detected, and optical elements foraberration correction (L2-L3, L5-L7, L10-L12 in FIG. 8 through FIG. 10)may also be driven based on the detected result. Such a technique isdisclosed, e.g., in W099/10917 (EP 1,020,897). EP 1,020,897 isincorporated herein by reference.

[0204] Additionally, it is preferable that the concentrations and/or thetotal amount of light-absorbing substances (gases such as oxygen (O₂),carbon dioxide (CO₂) and the like, water vapor (H₂O) and so on, aregiven as substances absorbing exposure beams and light-absorbingsubstances for the F₂ laser light of wavelength 157 μm) in the opticalpath of the illumination optical system, the optical path in the reticlechamber, the optical path in the projection optical system and theoptical path in the wafer chamber are controlled independently of eachother. For example, allowable concentrations and an allowable totalamount of the light-absorbing substances can be variably set up becausethe wafer chamber and the reticle chamber have short optical paths.Thus, the open/close mechanisms of the reticle chamber are simplifiedand contact with the outside air or mix-in of light-absorbing substancesis avoided because of the reticle exchange and the wafer exchange.Allowable concentrations and an allowable total amount of thelight-absorbing substances are harshly set up in response to theillumination optical system having a long optical path.

[0205] An F₂ laser can be incorporated in this embodiment which caninclude, nitrogen, rare gases such as helium (He), neon (Ne), argon (Ar)and the like as a permeable gas having a wavelength of 157 nm. Heliumgas is particularly superior in high permeability, stability of imagingcharacteristic of optical system and cooling property since its heatconductivity is about 6 times greater than that of nitrogen and itsfluctuation of dioptric index to pressure change is about ⅛greater thanthat of nitrogen gas. In this embodiment, the gas in the wafer chamberand the reticle chamber which fills the optical path of theinterferometers (wafer interferometer, reticle interferometer) and theinside of the projection optical system can be helium. And, the gas inthe optical path of the illumination optical system can be nitrogen gasin order to reduce the running cost. The gas used in the optical path ofthe illumination optical system can also be helium and the gas in thewafer chamber, the reticle chamber, and inside the projection opticalsystem can be nitrogen.

[0206] The following photopermeable optical materials constituting theillumination optical system and the projection optical system that canbe used include: lenses, parallel plane plates, micro fly's eye lensesand diffraction optical elements. In addition, fluorite (CaF₂), modifiedquartzs such as F-doped silica glass, F— and H-doped silica glass,OH-containing silica glass, F-doped and OH-containing silica glass andthe like can also be used. The photopermeable optical materialsconstituting the illumination optical system and the projection opticalsystem may also include the previously mentioned modified quartz. In theF-doped silica glass, the fluorine concentration is preferably 100 ppmor more, and more preferably in a range of 500 ppm-30,000 ppm. In theF-doped and H-doped silica glass, the hydrogen concentration ispreferably 5×10¹⁸ molecules/cm³ or less, and more preferably 1×10¹⁸molecules/cm³ or less. In the OH-containing silica glass, theconcentration of OH group is preferably in a range of 10 ppm-100 ppm. Inthe F-doped and OH-containing silica glass, the fluorine concentrationis preferably 100 ppm or more and the concentration of OH group ispreferably lower than the fluorine concentration. In this embodiment,the concentration of OH group is preferably in a range of 10 ppm-20 ppm.

[0207] When an image is formed by using a region free of the opticalaxis of the projection optical system, as in the present embodiment, anillumination optical system disclosed in Japan Kokai 2000-21765 (U.S.patent application 340,236 filed on Jul. 1, 1999) can be used as theillumination optical system. U.S. patent application 340,236 isincorporated hereby by reference.

[0208] Moreover, in this embodiment, a portion of the optical element inthe optical elements constituting the projection optical system isinclinable to the θ_(x), θ_(y) directions and/or movable in the XYplane. The optical elements may also be rotatably arranged in adirection of rotation (θ_(z) direction in the first and third imagingoptical systems) with the optical axis as the center by forming theoptical surfaces (refractive surfaces/reflecting surfaces) of theseoptical elements so as to have different powers in the meridionaldirections perpendicular to each other (dioptric plane/reflecting plane)of the optical elements (conducting an astigmatic surface processing).This arrangement results in correct asymmetrical aberrations such as anastigmatic difference on the optical axis (center astigmatism) of theprojection optical system, or a rhombic distortion of that.

[0209] For example, a construction in which an actuator and a drivingaxis are disposed along the tangential direction of the circumstance ofthe frame is arranged between a frame and a divided barrel such that theframe is driven to the divided barrel in the θ_(Z) direction. It ispreferable that the actuator is equal distant from the optical axis andarranged in a plurality of different locations at an equal-angle pitchin the circumferential direction (θ_(z) direction). A mechanism forrotating optical members with an astigmatic surface is disclosed inJapan Kokai 8-327895 (U.S. Pat. No. 5,852,518). U.S. Pat. No. 5,852,518is incorporated herein by reference.

[0210] Furthermore, a purge space may also be formed on the outside ofthe purge space of the illumination optical system and/or purge space ofthe projection optical system. In this case, the allowable concentrationand allowable total amount of light-absorbing substance of the purgespaces on the outside are set up more unexacting than the purge spaceson the inner side (the purge space of the illumination optical systemand/or the purge space of the projection optical system).

[0211] Additionally, a parallel plane plate is arranged on the waferside of the lens on the wafer side of the projection optical system. Theparallel plane plate may also be provided as a cover to the purge spaceof the projection optical system similar to the reticle side.

[0212] In addition to the F₂ laser light that supplies a pulse lighthaving a wavelength of 157 nm as provided for in this embodiment,implementing various other light sources is also possible. For example,the following light sources can be implemented a KrF excimer laser lightsupplying a light of wavelength 248 nm, and an ArF excimer laser lightsupplying a light of wavelength 193 m, and an Ar₂ laser light supplyinga light of wavelength 126 nm. A harmonic wave given by amplifying alaser light with a single wavelength in the infrared region oscillatedfrom a DFB semiconductor laser or a fiber laser or in the visible regionwith an Er-doped (or both Er-and Yb-doped) fiber amplifier that convertsthe light source to an ultraviolet light with a nonlinear opticalcrystal may also be used.

[0213] The present invention is applicable not only to micro-devicessuch as, semiconductor devices and the like, but also to an exposureapparatus for transferring circuit patterns from a mother reticle to aglass substrate, or a silicon wafer and the like, to manufacture areticle or a mask used in, e.g., a light exposure apparatus an EUVexposure apparatus, an X-ray exposure apparatus and an electron rayexposure apparatus and the like. Transmitting reticles are commonly usedin the exposure apparatus using DUV (deep ultraviolet) or VUV (vacuumultraviolet) light and the like. Silica glass, F-doped silica glass,fluorite, magnesium fluoride, or quartz crystal and the like are used asthe reticle substrate. In a proximity-mode X-ray exposure apparatus andan electron ray exposure apparatus and the like, transmitting masks(stencil mask, membrane mask) are used. A silicon wafer and the like isused as the mask substrate. Such exposure apparatus are disclosed in WO99/34255 CEP 1,043,625), WO 99/50712 (U.S. patent application 661,396filed on Sep. 13, 2000), WO 99/66,370, Japan Kokai 11-194479, JapanKokai 2000-12453, Japan Kokai 2000-29202 and so on. EP 1,043,625, U.S.patent application 661,396 and WO 99/66,370 are incorporated herein byreference.

[0214] The present invention is applicable not only to the manufactureof semiconductor devices, but also to an exposure apparatus which cantransfer device patterns onto a glass plate which are used in themanufacture of displays including liquid crystal display devices. Anexposure apparatus which transfers device patterns onto a ceramic waferand which are used in the manufacture of thin-film magnetic head, and anexposure apparatus used in the manufacture of image pickup devices suchas CCD and the like, and so on can also be applied.

[0215] The above-described present invention applies the scanning stepmode of operation. The present invention is also applicable to astep-and-repeat mode reduction projection exposure apparatus in whichmask patterns are transferred to a substrate in a static state of themask and the substrate. The substrate is then moved in successive steps.

[0216] An aperture stop is arranged in the third imaging optical systemin the previously mentioned embodiment. The aperture stop may also bearranged in the first imaging optical system. A field stop may also bearranged in at least one of the position of the intermediate imagebetween the first imaging optical system and the second imaging opticalsystem, and the position of the intermediate image between the secondimaging optical system and the third imaging optical system.

[0217] The projection magnification of the catadioptric projectionoptical system is given as a reduction ratio in previously mentionedembodiment. However, the projection magnification is not limited to thereduction ratio (magnification), it can also be an equal ratio (an unitmagnification) or an enlargement ratio (magnification). For example, ifthe projection magnification is the enlargement ratio, the opticalsystem can be arranged so that a light is incided from the side of thethird imaging optical system, a primary image of the mask or the reticleis formed by the third imaging optical system, a secondary image isformed by the secondary imaging optical system and a tertiary image isformed by the first imaging optical system on a substrate such as waferand the like.

[0218] As described above, in the catadioptric optical system, theprojection exposure apparatus and the exposure method including theoptical system of the previously mentioned embodiments, the opticaladjustment and mechanical design are improved. The aberrations beginningwith chromatic aberrations can be fully corrected. For example, aresolution of about 0.1 μm or less can be achieved by using a light witha wavelength of 180 nm or less in the vacuum ultraviolet wavelengthregion. Particularly, in the previous embodiments, the optical pathseparation is disposed in the vicinity of two intermediate images whichare formed by a mutual approach of the second imaging optical systemhaving a nearly equal (unit) magnification. Thus, the present inventionprovides for a small distance in the exposure region from the opticalaxis, i.e., the offset quantity, and is favorable in aberrationcorrection, miniaturization, optical adjustment, mechanical design,manufacturing cost and so on.

[0219] The previously mentioned embodiments provide for improvements inthe overlay accuracy of each exposure (each relay) and thesynchronization accuracy of the reticle and the wafer because thereticle surface and the wafer surface are parallel to each other andperpendicular to the direction of gravity. The optical adjustment andthe mechanical design is simple since there are only two optical axes.Thus, a transmission reflecting film having a low absorption and a highextinction ratio, a high-accuracy plate with a ¼wavelength and a prismwith homogeneity are not required and stray light caused by atransmission reflecting plane and the like also do not occur becausetransmission reflecting planes like a semi-transparent mirror or apolarizing beam splitter are not used. Also, because the reticle surfaceand the wafer surface are parallel to each other and perpendicular tothe direction of gravity.

[0220] Moreover, in the manufacturing method of micro-devices using theprojection exposure apparatus and the exposure method of the previouslymentioned embodiments, improved micro-devices can be manufactured viathe projection optical system in which the optical adjustment andmechanical design are simple. In addition, aberrations beginning withchromatic aberrations can be fully corrected and a high resolution ofabout 0.1 μm or less can be achieved.

[0221] While the invention has been described with reference topreferred embodiments thereof, it is to be understood that the inventionis not limited to the preferred embodiments or constructions. To thecontrary, the invention is intended to cover various modifications andequivalent arrangements. In addition, while the various elements of thepreferred embodiments are shown in various combinations andconfigurations, which are exemplary, other combinations andconfigurations, including more, less or only a single element, are alsowithin the spirit and scope of the invention.

What is claimed is:
 1. A catadioptric optical system forming a reducedimage of a first surface onto a second surface comprises: a firstimaging optical subsystem which is arranged in an optical path betweenthe first surface and the second surface and has a dioptric imagingoptical system to form a first intermediate image of the first surface;a first folding mirror which is arranged in the vicinity of a positionof forming the first intermediate image to deflect a beam prior to orafter the position where the first intermediate image is formed; asecond imaging optical subsystem for forming a second intermediate imagewith a magnification factor nearly equal to the first intermediate imagein the vicinity of a position of forming the first intermediate imagebased on the beam from the first intermediate image, the second imageoptical subsystem has a concave reflecting mirror and at least onenegative lens; a second folding mirror which is arranged in the vicinityof a position of forming the first intermediate image to deflect a beamprior to or after the position where the second intermediate image isformed; and a third imaging optical subsystem which is arranged in anoptical path between the second imaging optical subsystem and the secondsurface and has a dioptric imaging optical system to form the reducedimage onto the second surface based on the beam from the secondintermediate image.
 2. The catadioptric optical system of claim 1,wherein a reflecting surface of the first folding mirror and areflecting surface of the second folding mirror are positioned so thatthey do not overlap spatially.
 3. The catadioptric optical system ofclaim 2, wherein all lenses constituting the first imaging opticalsubsystem and all lenses constituting the third imaging opticalsubsystem are arranged along a single optical axis.
 4. The catadioptricoptical system of claim 3, wherein a magnification factor β2 of thesecond imaging optical subsystem satisfies the following condition:0.082<|β2|<1.20.
 5. The catadioptric optical system of claim 4, whereinthe following condition is satisfied: |L−L2|/|L1|<0.15,where a firstdistance between the first intermediate image and the concave reflectingmirror in the second imaging optical subsystem along the optical axis isdefined as L1, and a second distance between the second intermediateimage and the concave reflecting mirror in the second imaging opticalsubsystem along the optical axis is defned as L2.
 6. The catadioptricoptical system of claim 5, wherein the following condition is satisfied:0.20<|β|/|β1|<0.50,where a magnification of the catadioptric opticalsystem is defined as β, and a magnification of the first imaging opticalsubsystem is defined as β1.
 7. The catadioptric optical system of claim6, wherein the catadioptric optical system is a telecentric opticalsystem on both sides of the first surface and the second surface, andsatisfies the following condition: |E−D|/| E|<0.24,where a distancebetween a surface of the first imaging optical subsystem on a most imageside and an exit pupil position along the optical axis is defined as E,and a distance by air conversion from the surface of the first imagingoptical subsystem on the most image side to the concave reflectingmirror in the second imaging optical subsystem along the optical axis isdefmed as D.
 8. The catadioptric optical system of claim 7, wherein: thefirst intermediate image is formed in an optical path between the firstfolding mirror and the second imaging optical subsystem, and the secondintermediate image is formed in an optical path between the secondimaging optical subsystem and the second folding nirror.
 9. Thecatadioptric optical system of claim 8, wherein: 85% of the number oflenses in all lenses constituting the catadioptric optical system arearranged along the single optical axis.
 10. The catadioptric opticalsystem of claim 9, wherein: an intersection line of an extension planeof the reflecting surface of the first folding mirror and an extensionplane of the reflecting surface of the second folding mirror is set upso that an optical axis of the first imaging optical subsystem, anoptical axis of the second imaging optical subsystem and an optical axisof the third imaging optical subsystem intersect at one point.
 11. Thecatadioptric optical system of claim 10, wherein: the second imagingoptical subsystem has at least two negative lenses.
 12. The catadioptricoptical system of claim 11, wherein: the first folding mirror has a backsurface reflecting mirror for reflecting a beam from the first imagingoptical subsystem to the second imaging optical subsystem, and thesecond folding mirror has a back surface reflecting mirror forreflecting a beam from the second imaging optical subsystem to the thirdimaging optical subsystem.
 13. The catadioptric optical system of claim12, wherein: the catadioptric optical system forms the reduced image ona position deviating from a position of reference in an optical axis ofthe catadioptric optical system on the second surface.
 14. Thecatadioptric optical system of claim 1, wherein: a plurality of lensesconstituting the first imaging optical subsystem and a plurality oflenses constituting the third imaging optical subsystem are arrangedalong a single optical axis.
 15. The catadioptric optical system ofclaim 1, wherein a magnification β2 of the second imaging opticalsubsystem satisfies the following condition: 0.82<|β2|<1.20.
 16. Thecatadioptric optical system of claim 1, wherein the following conditionis satisfied: |L1−L2|/|L1|<0.15,where a first distance between the firstintermediate image and the concave reflecting mirror in the secondimaging optical subsystem along the optical axis is defined as L1, and asecond distance between the second intermediate image and the concavereflecting mirror in the second imaging optical subsystem along theoptical axis is defined as L2.
 17. The catadioptric optical system ofclaim 1, wherein the following condition is satisfied:0.20<|β|β1|<0.50,where a magnification of the catadioptric opticalsystem is defined as β, and a magnification of the first imaging opticalsubsystem is defined as β1.
 18. The catadioptric optical system of claim1, wherein the catadioptric optical system is a telecentric opticalsystem on both sides of the first surface and the second surface, andsatisfies the following condition: |E−D|/|E|<0.24,where a distancebetween a surface of the first imaging optical subsystem on a most imageside and an exit pupil position along the optical axis is defined as E,and a distance by air conversion from the surface of the first imagingoptical subsystem on the most image side to the concave reflectingmirror in the second imaging optical subsystem along the optical axis isdefmed as D.
 19. The catadioptric optical system of claim 1, wherein:the first intermediate image is formed in an optical path between thefirst folding mirror and the second imaging optical subsystem, and thesecond intermediate image is formed in an optical path between thesecond imaging optical subsystem and the second folding mirror.
 20. Thecatadioptric optical system of claim 1, wherein: the first intermediateimage is formed in an optical path between the first folding mirror andthe second imaging optical subsystem, and the second intermediate imageis formed in an optical path between the second imaging opticalsubsystem and the second folding mirror.
 21. The catadioptric opticalsystem of claim 1, wherein: 85% of the number of lenses in all lensesconstituting the catadioptric optical system are arranged along thesingle optical axis.
 22. The catadioptric optical system of claim 1,wherein an intersection line of an extension plane of a reflectingsurface of the first folding mirror and an extension plane of areflecting surface of the second folding mirror is set up so that anoptical axis of the first imaging optical subsystem, an optical axis ofthe second imaging optical subsystem and an optical axis of the thirdimaging optical subsystem intersect at one point.
 23. The catadioptricoptical system of claim 1, wherein the second imaging optical subsystemhas at least two negative lenses.
 24. The catadioptric optical system ofclaim 1, wherein: the first folding mirror has a back surface reflectingsurface for reflecting a beam from the first imaging optical subsystemto the second imaging optical subsystem, and the second folding mirrorhas a back surface reflecting surface for reflecting a beam from thesecond imaging optical subsystem to the third imaging optical subsystem.25. The catadioptric optical system of claim 1, wherein: thecatadioptric optical system forms the reduced image in a positiondeviating from a position of a reference optical axis of thecatadioptric optical system on the second surface.
 26. A catadioptricoptical system forming a reduced image on second surface comprises: afirst imaging optical subsystem with a first optical axis, which isarranged in an optical path between the first surface and the secondsurface and has a dioptric imaging optical system; a second imagingoptical subsystem with a concave reflecting mirror and a second opticalaxis, which is arranged in an optical path between the first imagingoptical subsystem and the second surface; and a third imaging opticalsubsystem with a third optical axis, which is arranged in an opticalpath between the second imaging optical subsystem and the second surfaceand has a dioptric imaging optical system, where the first optical axisand the second optical axis intersect with each other and the secondoptical axis and the third optical axis intersect with each other.
 27. Acatadioptric optical system forming a reduced image on second surfacecomprises: a first imaging optical subsystem with a first optical axis,which is arranged in an optical path between the first surface and thesecond surface and has a dioptric imaging optical system; a secondimaging optical subsystem with a concave reflecting mirror and a secondoptical axis, which is arranged in an optical path between the firstimaging optical subsystem and the second surface; and a third imagingoptical subsystem with a third optical axis, which is arranged in anoptical path between the second imaging optical subsystem and the secondsurface and has a dioptric imaging optical system, where the firstoptical axis and the third optical axis are located on a common axis.28. A projection exposure apparatus comprises: a projection opticalsystem which is arranged in an optical path between first surface andsecond surface that projects and exposes a pattern on a negative platelocated on a first surface onto a workpiece located on the secondsurface, and the projection optical system comprises: a first imagingoptical subsystem having a dioptric imaging optical system; a secondimaging optical subsystem having a concave reflecting mirror; a thirdimaging optical subsystem having a dioptric imaging optical system; afirst folding mirror arranged in an optical path between the firstimaging optical subsystem and the second imaging optical subsystem; anda second folding mirror arranged in an optical path between the secondimaging optical subsystem and the third imaging optical subsystem; wherethe first imaging optical subsystem forms a first intermediate image ofthe first surface into the optical path between the first imagingoptical subsystem and the second imaging optical subsystem, and thesecond imaging optical subsystem forms a second intermediate image ofthe first surface into the optical path between the second imagingoptical subsystem and the third imaging optical subsystem.
 29. Theprojection exposure apparatus of claim 28, wherein: the projectionexposure apparatus projects the pattern on the negative plate onto theworkpiece and exposes the pattern while the negative plate and theworkpiece are moved in the same direction.
 30. The projection exposureapparatus of claim 29, wherein: the first folding mirror has a firstreflecting surface, the second folding mirror has a second reflectingsurface, and the first reflecting surface and the second reflectingsurface are positioned so that they do not overlap spatially.
 31. Theprojection exposure apparatus of claim 30, wherein: the first and thesecond reflecting surfaces are substantially flat surfaces.
 32. Theprojection exposure apparatus of claim 29, wherein: the projectionoptical system forms a reduced image of the pattern onto the workpiece.33. The projection exposure apparatus of claim 29, wherein: at least oneof the first imaging optical subsystem and the third imaging opticalsubsystem contains an aperture stop.
 34. The projection exposureapparatus of claim 29, wherein: a plurality of optical members in thefirst imaging optical subsystem are arranged along a first optical axisextending in a straight line, the concave reflecting mirror in thesecond imaging optical subsystem are arranged along a second opticalaxis, and a plurality of optical members in the third imaging opticalsubsystem are arranged along a third optical axis extending in astraight line.
 35. The projection exposure apparatus of claim 29,wherein: the first imaging optical subsystem and the third imagingoptical subsystem have a common optical axis, and the first surface andthe second surface are orthogonal in a direction of gravity.
 36. Theprojection exposure apparatus of claim 29, wherein a magnification β2 ofthe second imaging optical subsystem satisfies the following condition:0.20<|β|/|β1|<0.50
 37. The projection exposure apparatus of claim 29,wherein the following condition is satisfied: 0.20<|β|/|β1|<0.50whereina magnification of the projection optical system is defined as β, and amagnification of the first imaging optical subsystem is defined as β1.38. The projection exposure apparatus of claim 29, wherein: theprojection optical system has a telecentric optical system on the sideof first surface and on the side of second surface, and a concavereflecting mirror in the second imaging optical subsystem is arranged inthe vicinity of a pupil surface of the projection optical system. 39.The projection exposure apparatus of claim 29, wherein: the firstintermediate image is formed in the optical path between the firstfolding mirror and a concave reflecting mirror in the second imagingoptical subsystem, and the second intermediate image is formed in theoptical path between the concave reflecting mirror in the second imagingoptical subsystem and th& second folding mirror.
 40. The projectionexposure apparatus of claim 39, wherein: the first intermediate imageand the second intermediate image are formed in both sides of a secondoptical axis of the second imaging optical subsystem.
 41. The projectionexposure apparatus of claim 29, wherein: a second optical axis of thesecond imaging optical subsystem is orthogonal to a first optical axisof the first imaging optical subsystem and a third optical axis of thethird imaging optical subsystem.
 42. The projection exposure apparatusof claim 41, wherein: the second optical axis of the second imagingoptical subsystem extends in a straight line.
 43. The projectionexposure apparatus of claim 29, wherein: an intersection line of anextension plane of a reflecting surface of the first optical pathfolding mirror and an extension plane of a reflecting surface of thesecond optical path folding mirror intersects with a first optical axisof the first imaging optical subsystem, a second optical axis of thesecond imaging optical subsystem and a third optical axis of the thirdimaging optical subsystem at one point.
 44. The projection exposureapparatus of claim 29, wherein: the first folding mirror has a backsurface reflecting surface for reflecting a beam from the first imagingoptical subsystem to the second imaging optical subsystem, and thesecond folding mirror has a back surface reflecting surface forreflecting a beam from the second imaging optical subsystem to the thirdimaging optical subsystem.
 45. The projection exposure apparatus ofclaim 29, wherein an image of the first surface is formed in a positiondeviating from a position of a reference optical axis of the projectionoptical system on the second surface.
 46. An exposure method forprojecting a pattern on a negative plate onto a workpiece via aprojection optical system comprises: directing an illuminating light inthe ultraviolet region to the pattern; directing the illuminating lightto a first imaging optical subsystem containing a dioptric imagingoptical system via the pattern to form first intermediate image of thepattern of the projection negative plate; directing the illuminatinglight from the first intermediate image to a second imaging opticalsubsystem containing a concave reflecting mirror to form a secondintermediate image; directing the illuminating a light from the secondintermediate image to a third imaging optical subsystem containing adioptric imaging optical system to form a second intermediate image;deflecting the illuminating light from the first imaging opticalsubsystem by a first folding mirror arranged in an optical path betweenthe first imaging optical subsystem and the second imaging opticalsubsystem; and deflecting the illuminating light from the second imagingoptical subsystem by a second folding mirror arranged in an optical pathbetween the second imaging optical subsystem and the third imagingoptical subsystem.
 47. The exposure method of claim 46, wherein: thepattern on the negative plate is projected onto the workpiece andexposed while the negative plate and the workpiece are moved in the samedirection for the projection optical system.
 48. A manufacturing methodof micro-devices comprises a lithographic process using the projectionexposure apparatus of claim
 29. 49. An imaging optical system forming animage of a first surface onto a second surface comprises at least onereflecting surface arranged between the first surface and the secondsurface, and the reflecting surface comprises a metallic reflective filmand a correction film which is arranged on the metallic reflective filmand corrects a phase difference caused by a difference of deflectedstate possessed by a reflected light from the metallic reflective film.50. The imaging optical system of claim 49, wherein: the correction filmcorrects an angular characteristic of the phase difference caused by thedifference of deflected states possessed by the reflected light from themetallic reflective film so as to obtain a desired distribution.
 51. Theimaging optical system of claim 50, wherein: the correction film has adielectric multilayer film.
 52. The imaging optical system of claim 51,wherein: the metallic reflective film contains aluminum.
 53. The imagingoptical system of claim 52, wherein: the reflecting surface is arrangedon an optical folding mirror for intersecting optical axes before andafter the reflecting surface intersect with each other.
 54. The imagingoptical system of claim 53, wherein the imaging optical system forms animage of the first surface onto the second surface based on a radiationof 200 nm. or less.
 55. The imaging optical system of claim 54, wherein:the imaging optical system is characterized by forming the image of thefirst surface in a position deviating from a position of a referenceoptical axis of the imaging optical system on the second surface. 56.The imaging optical system of claim 49, wherein: the correction film hasa dielectric multilayer film.
 57. The imaging optical system of claim49, wherein: the metallic reflective film contains aluminum.
 58. Theimaging optical system of claim 49, wherein: the reflecting surface isarranged on the optical folding mirror for intersecting optical axesbefore and after the reflecting surface intersect with each other. 59.The imaging optical system of claim 49, wherein: the imaging opticalsystem forms an image of the first surface onto second surface based ona radiation of 200 nm. or less.
 60. The imaging optical system of claim49, wherein: the imaging optical system is characterized by forming theimage of the first surface in a position deviating from a position of areference optical axis of the imaging optical system on the secondsurface.
 61. A projection exposure apparatus for projecting a pattern ona negative plate onto a workpiece and exposing the pattern using aprojection optical system, the image of the negative plate arranged onfirst surface is projected onto the workpiece arranged on second surfaceand exposed using the imaging optical system of claim 49 as theprojection optical system.
 62. A manufacturing method of micro-devicescomprises: a lithographic process using the projection exposureapparatus of claim
 61. 63. A projection exposure method for projecting apattern on a negative plate onto a workpiece using a projection opticalsystem and exposing the pattern comprises: a process for projecting animage of the negative plate arranged on the first surface is projectedonto the workpiece arranged on the second surface and exposing thepattern by using the imaging optical system of claim 49 as theprojection optical system.
 64. A projection exposure apparatus forprojecting a pattern on a negative plate arranged on a first surfaceonto a workpiece arranged on a second surface and for exposing thepattern, comprising: a projection optical system having at least onereflecting member arranged in an optical path between the first surfaceand the second surface, said reflecting member reflects a light so thata phase difference between a P polarized component and a S polarizedcomponent for the reflecting member substantially does not exist whenthe P polarized component and the S polarized component come to thephotosensitive substrate.
 65. A manufacturing method of micro-devicescomprises: a lithographic process using the projection exposureapparatus of claim
 64. 66. A projection exposure method for projectingand exposing a pattern on a negative plate arranged on a first surfaceonto a workpiece arranged on a second surface comprises: projecting thepattern onto the workpiece and exposing the pattern with a light passingthrough at least one reflecting member, and reflecting the light with areflecting member so that a phase difference between a P polarizedcomponent and a S polarized component for the reflecting membersubstantially does not exist when the P polarized component and the Spolarized component come to the sensitive substrate.